Answer:
Number Sense and Operations:
- 3/5 + 1/4 = 0.6 + 0.25 = 0.85
- If a number is increased by 25% and then decreased by 10%, the net change is an increase of 12.5%.
- 0.75 = 3/4
- √144 = 12
- (2/3) = (4/5) is not true. Cross-multiplying gives 4 ≠ 6.
Algebra:
6. Solve 2x - 5 = 3x + 7 for x:
2x - 5 = 3x + 7
-x = 12
x = -12
7. (x + 3)(2x - 4) = 2x^2 - 2x - 6x + 12 = 2x^2 - 8x + 12
8. Solve 2y + 7 = 3 for y:
2y + 7 = 3
2y = -4
y = -2
9. 3x + 5 = 17
10. 6x^2 + 9x = 3x(2x + 3)
Geometry:
11. Perimeter of a rectangle = 2 × (length + width) = 2 × (8 + 5) = 26 cm
12. In a triangle, the sum of the angles is 180°.
180° - (45° + 75°) = 60°
13. Area of a circle = π × r^2 = π × 6^2 = 36π cm^2
14. Volume of a rectangular prism = length × width × height = 4 × 6 × 9 = 216 cm^3
15. The sum of the angles in a quadrilateral is 360°.
110° + 70° + 100° + 80° = 360°, so it is a parallelogram.