Question

Help me! With number 9 and 10

Answer 1

9 is 82 blue v-necks and 43 red crew necks. 10 is for one angle it's 56 and fornthe other it is 34. For the first one, let a = blue v-necks and b = red crew necks. Then we have a system of equations: a + b = 125(total amount of shirts) and 7.95a + 8.95b = 1036.75(cost of shirts times how many shirts sold is the profit they got). Multiplyig the top equation by 8.95 we get 8.95a + 8.95b = 1118.75. Subtract that from the second and we get (8.95 - 7.95)a + (8.95 - 8.95)b = 82. The b is gone from that zero and a is being multiplied by one so that means a = 82. Plugging that into a + b = 125 and we get 82 + b = 125 ∴ b = 43. For the second question, since two angles are complementary, we can say ∠A = 90° - ∠B Then its says ∠A = 2∠B - 12. So putting the second ∠A def. into the first equation we get 2∠B - 12 = 90° - ∠B. Adding ∠B to both sides we get 3∠B -12 = 90°. Then adding 12 to both sides we get 3∠B = 102°. Divide by three and you get ∠B = 34 ∴ ∠A = 56.