Your Problem: 8.5+4(1-2.5k)=24.5 1st step: subtract 8.5 from both sides 4(1-2.5k)=24.5-8.5 4(1-2.5k)=16 2nd step: Divide both sides by 4 (1-2.5k)=16/4 (1-2.5k)=4 3rd step: Opening up the parentheses 1-2.5k=4 4th step: Subtract 1 from both sides -2.5k=4-1 -2.5k=3 4ht step: divide both sides by -2.5 k=-1.2
We do like the following: Set the first number is a and the second is b. We have two equations: a+2xb=24, 2xa+b=21 And we have 2xa+4xb=48 or 2xa=48-4xb So: 48-4xb+b=21 or -3xb=21-48=-27 and we got b=-27:(-3)=9 and a= 6 a=6 and b=9