Question

Monifer used substitution to solve this system of equations. Which equation could be the result of her first step? 3a +b=225 b=a-15

Answer 1

Answer:

Step-by-step explanation:

The given system of equations are:

$3a+b=225$                                         (1)

and $b=a-15$                                        (2)

Now, substituting the value of b from equation (2) in equation (1), we get

$3a+(a-15)=225$

⇒$3a+a-15=225$

⇒$4a=225+15$

⇒$4a=240$

⇒$a=\frac{240}{4}$

⇒$a=60$

Again, substituting the value of a=60 in equation (2), we get

⇒$b=(60)-15$

⇒$b=45$

Answer 2

3a + a - 15 = 225 . your substituting b(a-15) into the first equation. <span />