−5(1−5k)−4(2k+5), i got this problem on khan academy and can't figure it out

y=−9/2x+10

step-by-step explanation:

let's solve for y.

0−9x−2y=−20

step 1: add 9x to both sides.

−9x−2y+9x=−20+9x

−2y=9x−20

step 2: divide both sides by -2.

−2y

−2

=

9x−20

−2

y=

−9

2

x+10

x+y=90

x=30-y=x

step-by-step explanation:

if you understand you will get the answer