Can't understand simultaneous linear equation word problems.

[bleak locust]

might be easier to just think of it as now the mother is 3 times as old as her son and 8 years ago she was 5 times as old

once you have the simultaneous equations you can get the answer to the actual question

also consider your order of operations: i don't think it'd be as you've written the equations.

[winged yarrow]

so 3S + 8 = M?

[bleak locust]

think about it like this: now, M is 3*S.

then, M was 5*S.

then was 8 years ago

so what's the relationship between then and now?

(M-8)=5(S-8)

[slow ginkgo]

Ok so, we have 3 equations:

M = 3S

M = 5S

representing all possible ages where the mother is 5 times and 3 times as old

and M = S + C

where C is the age the mother was when the child was born

Looking for the right C value so that S2 intercept - S1 intercept = 8

for our intercepts we have: S1 + C = 5S1

and S2 + C = 3S2

S1 = C / 4

S2 = C / 2

C / 2 - C / 4 = 8

C / 4 = 8 ---> C = 32

We found C, now for our intercepts

S1 + 32 = 5S1

S1 = 8

S2 + 32 = 3S2

S2 = 16

so when the son was 8 , the mother would have been 40

and to get present values, can add 4 to each