Question

if xy=10, what is the value of 2 times x/y times y^2? Please explain your answers.

a) 5
b)8
c)10
d)12
e)20

Answer 1

e) 20... x/y * y^2 = xy. 2xy = 2*10 = 20

Answer 2

x = 10/y,

so$2 \times x/y \times y^2$

= $2 \times \frac{10/y}{y} \times y^2$

= $= 2\times 10y^2/y^2$

=$=2\times 10 =20$