Question

The given graph represents the total construction charges in dollars $\left(y\right)$ based on the area of land used in acres $\left(x\right)$.


Find the values of m and n.

• A. $m=\$4000,n=\$8000$
• B. $m=\$4200,n=\$8400$
• C. $m=\$3600,n=\$7200$
• D. $m=\$3300,n=\$6600$

Answer 1

The correct option is D $m=\$3300,n=\$6600$

Since the line is straight and passes through origin, it represents a proportional relationship.
So, $\frac{y}{x}$ must be a constant for all the points on the line.

For point $A\frac{y}{x}=\frac{1200}{4}=300$

The value of $\frac{y}{x}$ will be the same for points $B$ and $C$ as well.

For point $B,\frac{y}{x}=\frac{m}{11}=300$

$\Rightarrow m=300\times 11=\$3300$

For point $C,\frac{y}{x}=\frac{n}{22}=300$

$\Rightarrow n=300\times 22=\$6600$