If angle A and angle B are complementary, that would mean that their sum is 90 degrees. A + B = 90 . We know that angle A is 40, so 40 + B = 90. It becomes a one step equation. Subtract both sides by 40. 90 - 40 = 50. Angle B is equal to 50 degrees.
Here's the equation for one year: 0.03(8000) + 8000 For four years: 4(0.03(8000)) + 8000 0.12(8000) + 8000 To make it simpler/smaller: 1.12(8000) = 8960 You can make 960 more dollars, and you now have $8960