Warm Up Solutions

Solve.

Note

Problems 1–2

Q: What property can you use to solve proportions?

A: The cross-product property

$\begin{array}{rcl} (9) (30) & = & 22.5 x \\ \frac{270}{22.5} & = & \frac{22.5 x}{22.5} \\ x & = & 12 \end{array}$

$16 = \frac{w (4)}{9} 144 = 4 w w = 36$

Solve the equations for y.

$\frac{3}{5} x = z + y y = \frac{3}{5} x - z$

Note

Problems 3–4

Q: When problem 3 is equal to y, what linear form will it be in?

A: Slope-intercept form

$z x = k \sqrt{y} \frac{z x}{k} = \sqrt{y} y = {(\frac{z x}{k})}^{2}$