multiply the second equation by 4
4y=-x or x+4y=0
so now you have
x+8y=2
x+4y=0
subtract the second equation from the first.
4y=2
y=1/2 then solve for x
x+4y=0 or x=-2
What is the value of x + y in the solution to the system of equations below?
x + 8y = 2
y = -0.25x
I just need the best explanation so i can do all my other problems cause im confused.
5 answers
With substitution:
x + 8(-.025x) = 2
x + -.2x = 2
.8x = 2
x = 2/.8 = 2.5
x + 8(-.025x) = 2
x + -.2x = 2
.8x = 2
x = 2/.8 = 2.5
x + 8y = 2
y = -0.25x
Substitute.
x + 8(-0.25x) = 2
x - 2 = 2
x = 4
y = -0.25x
Substitute.
x + 8(-0.25x) = 2
x - 2 = 2
x = 4
Wow: three answers. Edgard, recommend you do some checking of the answers, that checking will teach you some algebra.
Ms Sue, yours should read:
x-2x=2
x=-2
Dr M: you didn't multipy .25 correctly...
Ms Sue, yours should read:
x-2x=2
x=-2
Dr M: you didn't multipy .25 correctly...
Thanks, Bobpursley. I goofed!