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put this solution on YOUR website!(a) 5x + 8 - 4x + 7
This is an expression as it does not have an = sign
Adding the like terms, we get, 5x - 4x + 8 + 7
= x + 15
(b) -6y + 12 + 7y -5
This is an expression as it does not have an = sign
==> (b) -6y + 12 + 7y -5
==> - 6y + 7y + 12 - 5
==> y + 7
==> y +7
c) 5x +8 - 4x = 7
This is an equation as = is present
==> 5x - 4x + 8 = 7
==> x + 8 = 7
==> x = 7 - 8 [adding -8 to both the sides]
==> x = - 1
d) -6y + 12 + 7y = -5
This is an equation as = is present
==> y + 12 = -5
==> y = -5 - 12 [ adding -12 to both the sides]
==> y = - 17
==> y = - 17