Thread: Word Problems Help.

1. The ratio of the measures of two complementary angles is 4 to 5. The smallest measure is increased by 10%. By what percent must the larger measure be decreased so that the two angles remain complementary?


2. The average of the three numbers x, y, and z is equal to twice the average of y and z. What is the value of x in terms of y and z?


3. Given that -3 <= x <= 2 and 20x^2 = y - 24, what is the smallest possible value for y?

1. 4x+5x= 90, x=10 First angle is 40 deg., the second is 50 deg., 10% of 40 is 4, so the second angle has to decrease by 4 deg., which is 8% of 50 deg.
2. (x+y+z)/3=2*(y+z)/2; cancel 2 on the right, (x+y+z)/3=y+z, mult by 3 both sides: x+y+z=3y+3z, subtr. y and z from both sides: x=2y+2z. Ta-dah!!
3.Check three points: -3, 0, 2 for x, and see which y is smallest.( answer is x=o, y=24-the smallest one)