Multiply both variables individually by the multiplied variable (x)... and you find yourself with -fx + hx.... Remember to bring that negative integer along too or the answere that I have without a negative integer won't count... I hope this clarified your understanding and question. As always good spiruts
180 = 3x + 5x + 2x +5
180 = 10x + 5
175 = 10x
x = 17.5
180 is how many degrees in a triangle
