Moniker used substitution to solve this system of equation. which equation could be the result of her first step

Step-by-step explanation:

We have the two equations as,

3a+b=225 and b=a-15

So in the substitution involved here its better if we substitute the second equation into first one.

We have the term b=a-15 so on directly substituting we get

4a=240,

a=60.

hence b would be 45.

In this way its better to substitute second one in the first one giving the following,

109 trust me

step-by-step explanation:

35x 3= 105

step-by-step explanation:

35+35= 70   70 + 35= 105