SOLUTION: What is the slope of the line x=-4t+7 and y=4t+2? Where does the line cross the x-axis? Where does the line cross the y-axis?

Algebra ->  Linear-equations -> SOLUTION: What is the slope of the line x=-4t+7 and y=4t+2? Where does the line cross the x-axis? Where does the line cross the y-axis?      Log On


   

Question 708155: What is the slope of the line x=-4t+7 and y=4t+2?
Where does the line cross the x-axis?
Where does the line cross the y-axis?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Two alternatives are:
working through t to get at the answer, or
getting rid of that t, expressing y as a function of x, and working as we normally do.

Where does the line cross the x-axis?
highlight%28Answer%29: At point (9,0).
The x-axis is the line y=0
y=0 --> 0=4t%2B2 --> 4t=-2 --> t=-1%2F2
t=-1%2F2 --> x=-4%28-1%2F2%29%2B7 --> x=2%2B7 --> highlight%28x=9%29
Where does the line cross the y-axis?
highlight%28Answer%29: At point (0,9).
The y-axis is the line x=0
x=0 --> 0=-4t%2B7 --> 4t=7 --> t=7%2F4
t=7%2F4 --> y=4%287%2F4%29%2B2%7D%7D+--%3E+%7B%7B%7By=7%2B2 --> highlight%28y=9%29

Alternatively,
x=-4t%2B7 --> x-7=-4t --> %28x-7%29%2F%28-4%29=t and
y=4%28x-7%29%2F%28-4%29%29%2B2 --> y=%284%2F%28-4%29%29%28x-7%29%2B2 --> y=%28-1%29%28x-7%29%2B2 --> y=-x%2B7%2B2 --> y=-x%2B9
Where does the line cross the y-axis?
The x-axis is the line y=0
0=-x%2B9 --> highlight%28x=9%29
Where does the line cross the y-axis?
The y-axis is the line x=0
x=0 --> y=-0%2B9 --> highlight%28y=9%29