The Variables x and y vary inversely, Write an equation that relates x and y

Question

y=-2 when x=5 so what is y when x=-7?

Answer 1

Two variables vary INVERSELY when as one variable INCREASES the other variable DECREASES. For example,

a) if you walk the same route to school every day (distance = speed x time), then an increase in your walking speed will decrease the time it takes for you to get there. Or if you increase the time it takes you to get there, then you must decrease your speed. Example: You live 2 miles from school and it takes you 40 minutes to get there walking at a speed of 1mph; how long would it take you to get back home after school if you jogged at a rate of 1.5 mph?

b) if you multiply a value by 5, then the inverse of multiplying by 5 is to divide by 5. Dividing by 5 is the same as multiplying by (1/5). Example 6x5 = 30, then 30 x (1/5) = 6 and 30 x (1/6) =5.

The inverse relation equation is X * Y = K, so Y = (K / X) . If Y=2 when X =5, the K = 10. So Y = K / X and

Y = 10 / -7, then Y = -1.428571429 (approximately) . No values for X, Y and K can equal zero.