a + 3a + 5a = 180 9a =180 a = 20
a + b + c = 180 b = 3a c = 5a Substituting the values of b and c into the first equation. a + 3a + 5a = 180 or 9a = 180 so that a = 20 then b = 3a = 3*20 = 60 and c = 5a = 5*20 = 100
a = 20 b = 60 c = 100
5a + 2 = 7 subtract 2 from both sides: 5a = 5 divide both sides by 5: a = 1
From your description, I get: a + b + c = 180b - 3a c = 5a You have two equations and three unknowns, which is unsolvable.
5a = 22 Divide both sides by 5: a = 4.4
45
Gathering like terms together, this can be rewritten: 9a = 180 Dividing both sides of the equation by 9: a = 20
If: -5a = 300 Then: a = -60
5a+5=6a-7
4a + a = 25 add 4a and a 5a = 25 then divide 25 by 5 a = 5
(5a).7 = -23 7(5a) = -23 35a = -23 a = -23/35 a= -0.657 (3 d.p.)