The sum of the present age of a mother and her son is 35 and the difference is 25 years. find their present age.(By substitution or elimination method).

Son = 5 years old

Mum = 30 years old

Step-by-step explanation:

Let the Mum be M and the Son be S;

--- Sum

-- Difference

Required

Find M and S (their ages)

Using elimination method; Add both equations to eliminate S

----------------

Solve for M

Substitute 30 for M in

Solve for M

Hence:

Son = 5 years old

Mum = 30 years old

option c) graph of line going through 1, 4 and 3, 10

step-by-step explanation:

let y equal to margo's coin collection

let x equal to number of years

at the begining x=0, y=1 → point=(x,y)→point=(0,1)

she adds 3 coins per year, then y=1+3x

at x=1, y=1+3(1)=1+3→y=4→point=(x,y)→point=(1,4)

at x=3, y=1+3(3)=1+9→y=10→point=(x,y)→point=(3,10)

the graph of line going through (1, 4) and (3, 10), then the option c is the correct.

35-60 students are taking math.