IB- GRADE 9 QUARTERLY REVIEW QUESTIONS
1. Which of the following describes the figure below?
Answer: B
Distance=โฃ7โ(โ1)โฃ
Distance=โฃ7+1โฃ
Distance=โฃ7+1โฃ
Distance=โฃ8โฃ
So, the distance between -1 and 7 is 8 units.
ANSWER: A
3. If RS=38; and QS=86.4, find QR.[A] 38.4[B]124.4[C] 38[D] 48.4
QR=QSโRS
QR=86.4โ38
QR=86.4โ38
QR=48.4
ANSWER = D
4. Solve: In the figure (not drawn to scale), (๐๐) โ bisects โ LMN, m โ LMO=18x-34 and M โ NMO=x+136. Solve for x and find m โ LMN[A] 6,44[B]10,214[C] 6,74[D] 10, 292
(๐๐) โ bisects โ LMN, SO BY ANGLE BISECTOR THEOREM
m โ LMO= M โ NMO
18x-34 = x+136.
18X-X = 136+34
17X=170
X=10
m โ LMO = 18X -34 = 18 X 10 -34 = 180 -34 = 146
M โ NMO=x+136 = 10 + 136 =146
M โ LMN= 146 + 146 = 292
ANSWER : D
The midpoint formula for one-dimensional coordinates is:
M = (๐+๐)/2
2 = (โ5+๐)/2
4 = โ5+๐
X = 9
ANSWER: B
6. Ifโ A and โ B are supplementary angles and m โ A = 3m โ B find m โ A and m โ B.[A] 120,60[B] 67.5.22.5[C] 60, 30[D] 135,45
Given that mโ A=3mโ B,
mโ A+mโ B=180ยฐ
3mโ B+mโ B=180 ยฐ
4mโ B=180 ยฐ
mโ B=180"ยฐ" /4
mโ B=45 ยฐ
mโ A=3mโ B
mโ A=3ร45 ยฐ
mโ A=135 ยฐ
ANSWER: D
[A] โ BEC and โ CED are adjacent angles.
Adjacent angles are angles that share a common side and a common vertex but do not overlap. In the figure, โ BEC and โ CED share the common side EC and the common vertex E, but they do not overlap. So, this statement is true.
[B] โ AEB = 72ยฐ
Since โ AED = 108ยฐ, and โ AED and โ AEB are supplementary angles (forming a straight line), then โ AEB = 180ยฐ - 108ยฐ = 72ยฐ. So, this statement is true.
[C] โ AEB and โ DEC are vertical angles.
Vertical angles are formed by intersecting lines and are opposite each other. In the figure, โ AEB and โ DEC are opposite each other. So, this statement is TRUE.
[D] mโ BEC = 72ยฐ
Since โ AED = 108ยฐ, and โ AED and โ BEC are Vertically opposite angles then โ BEC = โ AED = 108ยฐ So, this statement is false.
ANSWER: D the false statement is m โ BEC=72ยฐ
8. IF โ A and โ B are complementary angles and mโ A=5mโ B find m โ A and m โ B.[A] none of these[B] 144ยฐ,36ยฐ[C] 150ยฐ,30ยฐ[D] 72ยฐ,18 ยฐ
mโ A=5mโ B
mโ A + mโ B = 90ยฐ (COMPLEMENTARY ANGLES)
mโ B+5mโ B = 90ยฐ
6mโ B = 90ยฐ
mโ B =90/6
mโ B = 15ยฐ
mโ A=5mโ B
mโ A=5 X 15ยฐ = 75ยฐ
ANSWER: A
9. Find the distance between points P(-4, 2) and Q(5,-3) .[A] 2โ17[B] โ106[C] 10[D] โ2
The distance between points P(-4, 2) and Q(5,-3)
D = โ(ใ"(x2" โ"x1" )ใ^2+ใ"(y2" โ"y1" )ใ^2 )
D = โ(ใ"(5" +4)ใ^2+ใ"(โ" 3โ2)ใ^2 )
D = โ(ใ"(9" )ใ^2+ใ"(" โ5)ใ^2 )
D = โ(81+25)
D = โ106
ANSWER: B
10. Find the coordinates of the midpoint of the segment connecting H(-2,-4) and K(-12,6)[A] (5,5)[B] (-7,1)(C) (10, 1)[D] (-14, 2)
H(-2,-4) and K(-12,6)
Mid point Formula
M = ("x2 + x1" /"2" , ("y2 +y" 1)/"2" )
M = (("โ12 โ" 2)/"2" , "6โ4" /"2" )
M = ((โ14)/"2" , 2/"2" )
M = (-7, 1)
ANSWER: B
11. Find the values of x, y, and z.[A] x=91 , y=89 z=66[B] x=91 y=89 z = 49[c] x=89 , y=91 z=66[ D]x=89,y=91,z=49
โ BAC + โ ABC = โ BCD=Y
65ยฐ +26ยฐ = 91ยฐ =Y
X+Y=180ยฐ (LINEAR PAIR)
X+91ยฐ = 180ยฐ
X=180-91=89ยฐ
23ยฐ + Z+Y=180ยฐ (ANGLE SUM PROPERTY OF TRIANGLE)
23ยฐ + Z+91ยฐ =180ยฐ
Z = 180ยฐ - 114ยฐ = 66ยฐ
ANSWER: C
12. Find a and b.[A] a=33,57 [C] a=33,b=78[B] a=45,b=57 [D] a=45, b = 33
โ C = 90ยฐ = 45 ยฐ +45 ยฐ
b + 78 +45 = 180 ยฐ (ANGLE SUM PROPERTY OF A TRIANGLE)
b = 180 ยฐ - 123 ยฐ=57 ยฐ
LINEAR PAIR +78 = 180 ยฐ
LINEAR PAIR = 180 -78 ยฐ = 102 ยฐ
102 ยฐ+a + 45 ยฐ = 180 ยฐ
a = 180 โ 147 = 33 ยฐ
ANSWER: A
13. In A ABC, mโ A=64 ยฐ and m โ C=52 ยฐ, Calculate m โ B.[A] 74 ยฐ[B] 26 ยฐ[C] 244 ยฐ[D] 64 ยฐ
Angle sum property of a triangleโ B=180ยฐ โ(64ยฐ +52ยฐ)
โ B=180ยฐ โ116ยฐ
โ B=64ยฐ
ANSWER : D
14. Classify the triangle with sides of length 15, 15, and 15.[A] isosceles[B] scalene[C] straight[D] equilateral
A triangle with all three sides of equal length is called an equilateral triangle. So, a triangle with sides of length 15, 15, and 15 is an equilateral triangle.
ANSWER: D
15. Classify the triangle with angles measuring 84ยฐ, 65ยฐ and 31ยฐ [A] straight [B] obtuse[C] right [D] acute
this triangle is classified as an "acute triangle". An acute triangle is a triangle where all three angles are less than 90ยฐ.
ANSWER: D
16. Graph: y=5x+5
17. Find the slope of the line passing through the points A(-7,-3) and B(-4,5)[A] (โ2)/11 [B] 13/8 [C] 3/( 8) [D] 8/3
SLOPE = ("Change in" ๐)/("Change in" ๐)
m = "y2 โy1" /"x2 โx1"
m = ("5+" 3)/(" โ4+" 7)
m= 8/3
ANSWER: D
18. Which of the lines is not perpendicular to 2x+y=8?[A] Y - ๐/2 = 6[B] 2y-x=4[C] X โ 2Y =3[D] 2x-y=4
Two lines are perpendicular if and only if the product of their slopes is -1.
[2x + y = 8] ๏จ[y = -2x + 8]๏จ M= -2
[A] Y - ๐/2 = 6 ๏จ Y = ๐/2 + 6๏จ M = 1/2[B] 2y-x=4 ๏จ Y = ๐/2 +2 ๏จ M = 1/2
[C] X โ 2Y =3 ๏จ Y = 1/2X+ 3/2 ๏จ M = 1/2[D] 2x-y=4 ๏จ Y= 2X+4 ๏จ M = 2
the line not perpendicular to (2x+y=8) is line [D] (2x-y=4).
ANSWER: D
19. In the figure shown, PQ-18 centimeters ST=6 centimeters and mโ QRP=60ยฐ. Find mโ S[A]30ยฐ[B] 90ยฐ[C] 60ยฐ[D] 120ยฐ
mโ QRP=60ยฐ= mโ TRS (Vertically opposite angles)
mโ RTS=90ยฐ
Angle sum property of a triangle
mโ TRS + mโ RTS + mโ RST=180ยฐ
60ยฐ+90ยฐ+ mโ S =180ยฐmโ S =180ยฐ- 150ยฐ
mโ S =30ยฐ
ANSWER: A
20. Two pentagons are similar. The perimeter of one is 42 m and that of the other is 105 m. Find the ratio of the sides of the pentagons.[A] 1:2.5[B] 1:2[C] 1:6.25[D] 2:5
If two pentagons are similar, it means their corresponding sides are proportional.
"Perimeter of smaller pentagon" /"Perimeter of LARGER pentagon" ="Ratio of sides of smaller pentagon" /"Ratio of sides of LARGER pentagon"
42/105= ๐ /1
R = 2/5 = 1/2.5
each side of the smaller pentagon is 2/5 times the length of the corresponding side of the larger pentagon.
RATIO = 1/2.5
ANSWER: A 1:2.5
21. In the figure shown, (๐ต๐ถ) ฬ ||(๐ท๐ธ) ฬ , AB= 4 yards, BC=6 yards, AE=20 yards, and DE=24 yards. Find BD.[A] 15 yd[B] 12 yd[ C]5 yd[D]16yd
In similar triangles, corresponding sides are proportional.
๐จ๐ฉ/๐จ๐ซ = ๐ฉ๐ช/๐ซ๐ฌ
๐จ๐ฉ/(๐จ๐ฉ+๐ฉ๐ซ) = ๐ฉ๐ช/๐ซ๐ฌ
๐/(๐+๐ฉ๐ซ) = ๐/๐๐
๐+๐ฉ๐ซ = 16
BD = 16-4 = 12 YARDS
ANSWER: B
22. Find the values of x and y.[A] x=8 ยฐ y=86 ยฐ[C] x =86ยฐ; y =94ยฐ[B]x=86 ยฐ;y=66 ยฐ[D] x=8 ยฐ; y=94 ยฐ
LINEAR PAIR OF ANGLES
94ยฐ+Z = 180ยฐ
Z = 180 ยฐ -94 ยฐ= 86ยฐ
IN AN ISOSCELES TRIANGLE, THE ANGLES OPPOSITE TO EQUAL SIDES ARE EQUAL.
Y = 86ยฐ
ANGLE SUM PROPERTY OF A TRIANGLE
86 ยฐ+86 ยฐ+X = 180 ยฐ
X = 180 ยฐ-172 ยฐ
X = 8 ยฐ
ANSWER: A
The triangle inequality theorem, which states that the sum of the lengths of any two sides of a triangle must be greater than the length of the remaining side.
[A] 24 cm, 15 cm, 8 cm:
24 + 15 > 8 (True)
24 + 8 > 15 (True)
15 + 8 > 24 (True) All three conditions are true, so these lengths can form a triangle.
[B] 6 cm, 19 cm, 13 cm:
6 + 19 > 13 (True)
6 + 13 > 19 (True)
19 + 13 > 6 (True) All three conditions are true, so these lengths can form a triangle.
[C] 19 cm, 6 cm, 14 cm:
19 + 6 > 14 (True)
19 + 14 > 6 (True)
6 + 14 > 19 (True) All three conditions are true, so these lengths can form a triangle.
[D] 15 cm, 24 cm, 7 cm:
15 + 24 > 7 (True)
15 + 7 > 24 (False)
24 + 7 > 15 (True) The second condition is false, so these lengths cannot form a triangle.
So, the options [A], [B], and [C] are valid triangles, but option [D] is not.
24. Find the largest side of the triangle, (not drawn to scale)[A] (๐ด๐ถ) ฬ [B] (๐ต๐ถ) ฬ [C] (๐ด๐ต) ฬ [D] not enough information
โ BAC = 180ยฐ-82ยฐ=98ยฐ
SUM OF ALL THE ANGLES OF A TRIANGLE = 180ยฐ
โ ABC = 180ยฐ โ (98ยฐ+51ยฐ) = 180ยฐ โ 149ยฐ = 31ยฐ
SIDE OPPOSITE TO LARGEST ANGLE IS LARGEST SIDE.
SO SIDE OPPOSITE TO 98 ยฐ IS (๐ต๐ถ) ฬ
ANSWER: B
25. Find mโ 1 in the figure below. (๐๐) โก and (๐ ๐) โก are parallel.[A] 61 ยฐ[B]109 ยฐ[C]29 ยฐ[D] 119 ยฐ
Corresponding angles are equal = 61ยฐ
Linear pair of angles
m โ 1 + 61 ยฐ = 180 ยฐ
m โ 1= 180 ยฐ-61 ยฐ
m โ 1 = 119 ยฐ
ANSWER: D
26. Refer to the figure shown. Which of the following statements is true?
ANSWER: [B]
(๐๐) ฬ = (๐๐) ฬ (Given)
(๐๐) ฬ = (๐๐) ฬ (given)
โ UVT = โ WVX (vertically opposite angles)
THEN โTUV โ โWXV BY SAS
ANSWER: D
27. The triangles below are similar. Find the length of x.[A] 70[B] 73.5[C] 5.7[D] 73
๐๐/๐๐ = ๐ฟ/๐๐ = ๐๐/๐
๐/๐๐ = ๐๐/๐ฟ๐
14*X = 49 X 20
X = 980/14
X = 70
ANSWER: A
28. Triangles ABC and XYZ are similar with โ A = โ X and โ B\= โ Y. IF AB, BC, and AC are 8 inches, 9 inches, and 11 inches long, respectively, and YY is 15 inches long, find XZ. (Answer to the nearest tenth.)[A] 4.8 in.[B] 5.9 in.[C] 16.9 in.[D] 20.6 in.
AC corresponds to XZ and XY corresponds to AB
๐จ๐ฉ/๐ฟ๐ = ๐จ๐ช/๐ฟ๐
๐/๐๐ = ๐๐/๐ฟ๐
8*XZ = 11 X 15
XZ = 165/8
XZ = 20.625
ANSWER: D
29. Solve for x : (๐+๐)/๐ = ๐/๐[A] -21[B] (โ๐)/๐ [C] (โ๐)/๐[D] ๐๐/๐
(๐+๐)/๐ = ๐/๐
9(x+7) = 7 x6
9x+63=42
9x= 42-63
9x=-21
X = (โ๐)/๐
ANSWER: B
Find the geometric mean of 18 and 2A 6B 9C 10D 4
Geometric Mean of 2 and 18
If a and b are 2 numbers The geometric mean of a and b is โ๐๐
Applying the formula
GM of 2 and 18 is
โ(2 x 18) =โ36 =6
The answer : A
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