# ACT Aspire Math: Identifying the Graph of a Reflected Line

The graph of y = -x + 5 is reflected across the x-axis.

Which of the following shows the reflected graph?

ACT Aspire | Math |

ACT Aspire Math | Functions |

Math | Functions |

Product Type | ACT Aspire |

Test Prep | ACT Aspire ACT Aspire Math |

### Transcript

We advise against it since to see the reflection from

the right angle you'd probably have to smash your face

up against your desk Instead let's consider what rules we

know about transform ations But when we reflect a point

across the x axis we multiply the original y coordinate

by negative one Find a new why co ordinate while

the x coordinate remains unchanged In other words the rule

to remember about reflecting across the x axis is that

the point x why would be transformed into the point

x negative y very important concept here were given a

line and an equation for that line No why calls

they could expose five rather than a set of points

However we can imagine that line is having many different

points on it in reflecting those many different points across

the x axis We know that for each point will

retain the same x values but corresponding why values should

be multiplied by negative one Right So our new equation

then will demonstrate those new negative y values right there

multiplied by negative one So we get negative y equals

negative x plus five Well to graft this equation no

we just put it into slope intercept form y equals

mx plus b That means we'll need to multiply both

sides by negative one so we can isolate that Why

there And we get y equals negative The quantity there

of negative exposed five or y equals x minus five

So the reflected graph corresponds to the equation Y equals 00:01:40.281 --> [endTime] x minus five and that's pretty much it