Question

A store owner spends 7x + 13 dollars on two orders of boxes of light bulbs, including shipping.

Answer 1

Answer:

$B = 4x + 8$

A box = $11

Step-by-step explanation:

Given

$Total = 7x + 13$

Represent the first order with A and the second with B.

So, we have:

$A = 3x + 5$

Solving (a): Find B.

To find B, we make use of:

$A + B = Total$

Make B the subject

$B = Total - A$

Substitute values for Total and A

$B = 7x + 13 - (3x + 5)$

Open bracket

$B = 7x + 13 - 3x - 5$

Collect Like Terms

$B = 7x - 3x + 13 - 5$

$B = 4x + 8$

Solving (b): Cost of a box of light bulb

This means that:

$Total = 90$

Substitute 7x + 13 for Total

$7x + 13 = 90$

Collect Like Terms

$7x = 90 - 13$

$7x = 77$

Make x the subject

$x = \frac{77}{7}$

$x = 11$