SOLUTION: Hi . im stuck on this maths question. equation: x + (x+1) + (x+2) = y use the equation to help you write the missing expressions in terms of y. (x+5) + (x+6) + (x+7) = 2

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Hi . im stuck on this maths question. equation: x + (x+1) + (x+2) = y use the equation to help you write the missing expressions in terms of y. (x+5) + (x+6) + (x+7) = 2      Log On


   

Question 191914: Hi . im stuck on this maths question.
equation:
x + (x+1) + (x+2) = y
use the equation to help you write the missing expressions in terms of y.
(x+5) + (x+6) + (x+7) =
2x + 2(x+1) + 2(x+2) =
(x+a) + (x+1+a) + (x+2+a) =
how would you work it out? please explain it step by step
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
equation:
x + (x+1) + (x+2) = y
use the equation to help you write the missing expressions in terms of y.
combine terms and solve for x
3x + 3 = y
3x = y - 3
x = (y%2F3-1)
Substitute for x, and combine like terms in the following:
:
(x+5) + (x+6) + (x+7) =
((y%2F3-1)+5) + ((y%2F3-1)+6) + ((y%2F3-1)+7) =
3(y%2F3) - 1 + 5 - 1 + 6 -1 + 7 = y + 15
:
:
2x + 2(x+1) + 2(x+2) =
2(y%2F3-1) + 2((y%2F3-1)+1) + 2((y%2F3-1)+2 =
2y%2F3-2 + 2y%2F3-2 + 2 + 2y%2F3-2 + 4 =
6y%2F3 - 2 - 2 + 2 - 2 + 4 = 2y
:
:
(x+a) + (x+1+a) + (x+2+a) =
y%2F3-1+a + y%2F3-1+1+a + y%2F3-1+2+a =
3(y%2F3) - 1 - 1 + 1 - 1 + 2 + a + a + a = y + 3a
:
;
did you understand these steps?