+1347 I keep getting the wrong answer on this one.
Find the distance between the x-intercept and the y-intercept of the graph of the equation 3x - 7y = 21 + 2x - 5y.
Find the distance between the x-intercept and the y-intercept of the graph of the equation 3x - 7y = 21 + 2x - 5y.
3x - 7y = 21 + 2x - 5y
Combine like terms. –7y + 5y = 2x – 3x + 21
–2y = –x + 21
Multiply both sides by –1
this isn't necessary but it
makes it easy to work with.
Easier for me, anyway, LOL. 2y = x – 21
Set y = 0 and solve for x x = 21 That's your x-intercept.
Set x = 0 and solve for y y = –10.5 That's your y-intercept.
Those are the values of the two legs of a right triangle, with the origin being the right angle.
If you draw it on a graph, it's obvious.
The line between the x- and y- intercepts is the hypotenuse of that right triangle.
Pythagoras' Theorem c2 = (21)2 + (–10.5)2
c2 = 441 + 110.25 = 551.25
I used my calculator to
get this square root. c = 23.48
.
