Algebra
posted by Liz on .
How do you solve and graph these equations?
y = 4x + 5
x  2y = 4

y = 4 x + 5, through (0,5) slope 4
2y = x  4
y = (1/2) x  2 , through(0,2) slope (1/2)
now subtract second from first to get rid of y
0 = 3.5 x +7
x = 2
then y = 8+5 = 3
so they cross at (2,3)
check
y = 4x + 5
3=4(2)+5??
3=8+5 yes
x  2y = 4
2 2(3) =4 ??
2 +6 = 4 sure enough