Answer:
7. The area should be 32. Multiply 5 by 4 to get 20. Find the missing length to multiply by 3, which is 4, and multiply. 3 * 4 = 12. Add 20 + 12 and get 32 cm.
8. The area should be 70. You did pretty well, but when finding the area of a triangle, divide the product by 2, or multiply by 0.5. 5 * 8 = 40/2 or 40 * 0.5 which both equal 20. 50, plus the area of the triangle, 20, will get you 70.
