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Example 4.7 from Elementary Algebra, 4.1 Use the Rectangular Coordinate System

Use the Rectangular Coordinate System: example 4.7

Complete Table 4.6 to find three solutions to the equation $5 x - 4 y = 20$ .

$5 x - 4 y = 20$
$x$	$y$	$(x, y)$
0
	0
	5

Table 4.6

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution
Substitute the given value into the equation $5 x - 4 y = 20$ and solve for the other variable. Then, fill in the values in the table.

The results are summarized in Table 4.7.

$5 x - 4 y = 20$

$x$ $y$ $(x, y)$

0 $−5$ $(0, −5)$

4 0 $(4, 0)$

8 5 $(8, 5)$

Table 4.7

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Complete the table to find three solutions to this equation: $2 x - 5 y = 20$ .

$2 x - 5 y = 20$
$x$	$y$	$(x, y)$
0
	0
$−5$

How did it go?

PreviousUse the Rectangular Coordinate System: example 4.6 Next Use the Rectangular Coordinate System: example 4.8

From Elementary Algebra (1st edition) by OpenStax (Rice University), section 4.1, licensed under CC BY 4.0. Original at openstax.org. We split the solution into steps; the words, numbers and figures are the book's. OpenStax doesn't endorse this site.