Home > A2C > Chapter 1 > Lesson 1.1.3 > Problem1-38

1-38.

As you have found when using a graphing calculator, equations must be solved for y; that is, they must be written in $y$−form. Rewrite each equation below so that it can be entered into a graphing calculator.

1. $x = 3y + 6$

Subtract $6$ from both sides.How can you get $y$ by itself?

$y=\frac{1}{3}x-2$

1. $x = 5y − 10$

See part (a).

1. $x = y^2$

Notice that $y$ is squared.
How many answers should you expect?

$y=\sqrt{x}\text{ or }-\sqrt{x}$

1. $x = 2y^2− 4$

$2y^2=x+4$

$y^2=\frac{1}{2}x+2$

How many answers should you expect? How can you write a compact solution to show them?

$y=\pm\sqrt{\frac{1}{2}x+2}$

1. $x = (y − 5)^2$

How do you undo squaring? Continue to solve for y as you did in parts (c) and (d).

Rewrite each equation and enter it in the eTool below. Check your answers using the eTool.
Click the link at right for the full version of the eTool: A2C 1-38 HW eTool