Exercise 25 Page 465

To solve the proportion, we will start by using the Cross Products Property. Remember that we will need to treat

2 x + 5

as a single quantity in the cross multiplication process.

\frac{2 x + 5}{1 0} = \frac{4 2}{2 0}

Cross multiply

(2 x + 5) 20 = 10 (42)

From here, we will continue solving for

x

(2 x + 5) 20 = 10 (42)

$LHS / 10 = RHS / 10$

(2 x + 5) 2 = 42

Distribute $2$

4 x + 10 = 42

$LHS - 10 = RHS - 10$

4 x = 32

$LHS / 4 = RHS / 4$

x = 8

Therefore, the solution for the given equation is

x = 8 .