Answer:
<em>4a ) Difference ⇒ $ 63.24,</em>
<em>4b ) 4 children</em>
Step-by-step explanation:
4a ) If the number of children is represented by the value of x, let us substitute a family of 2 children as value of x into this equation we are given;
y = 21.08 * ( 2 ) + 85.15 ⇒ Multiply 21.08 by 2,
y = 42.16 + 85.15 ⇒ Combine like terms,
y = 127.31
If y ⇒ amount spent on grocery's, let us solve for the amount spent on 5 children, and subtract from this amount;
y = 21.08 * ( 5 ) + 85.15 ⇒ Multiply 21.08 by 5,
y = 105.4 + 85.15 ⇒ Combine like terms,
y = 190.55
Difference; 190.55 - 127.31 = 63.24,
<em>Solution; Difference ⇒ $ 63.24</em>
4b ) If the amount is $ 169.47, let us plug it into our given equation provided amount spent on groceries ⇒ y;
169.47 = 21.08x + 85.15 ⇒ Subtract 85.15 from either side of equation,
21.08x = 84.32 ⇒ Divide either side 21.08,
x = 4 children
<em>Solution; 4 children</em>
