1963 TMTA High School Algebra I Contest Problem 17

Problem

If the graph if the equation $5x+ky=9$ passes through the point $(3, -1,)$ what is the value of $k?$

$\text{(A)} \quad 24 \quad \text{(B)} \quad 16 \quad \text{(C)} \quad -6 \quad \text{(D)} \quad 6 \quad \text{(E)} \quad 4$

Plug in $(3, -1)$ into the line's equation to get $5(3)+k(-1)=9.$ We see that $k$ is equal to $\boxed{\text{(C)} \quad -6}.$

1963 TMTA High School Mathematics Contests (Problems)
Preceded by Problem 16	TMTA High School Mathematics Contest Past Problems/Solutions	Followed by Problem 18