Answer:
x=-6
y=3
Explanation:
y=-4x-21
8x+8y=-24
y=-4x-21
8x+8(-4x-21)=-24
y=-4x-21
-24x-168=-24
y=-4x-21
x=-6
y=-4(-6)-21
x=-6
y=3
x=-6
(-6,3) this is in point form in case you need it
Your answer would be r = 12/7 ≈ 1.71
Firstly you need to write an equation involving r and t. They tell you that r varies inversely with t, which means r = k/t, where k is some constant.
We can find k by substituting in the values for r and t that they give us:
r = k/t
2 = k/(-6)
-12 = k
Now the equation is r = -12/t. We can then substitute in t as -7 to get the final answer:
r = -12/t
r = -12/(-7)
r = 12/7 ≈ 1.71
I hope this helps!