Question

Determine whether or not the given pairs of values are solutions of the given linear equations in two unknowns. 5x + 4y = 21 , (1,4) (3, 1\4)Is (1,4) the solution of the equation 5x + 4y = 21?

Answer 1

The given equation is expressed as

5x + 4y = 21

To determine if (1, 4) is a solution of the equation, we would substitute x = 1 and y = 4 into the equation. If we get 21 on the right, it means that (1,4) is a solution. We have

5(1) + 4(4)

5 + 16 = 21

Since we got 21, it means that (1, 4) is a solution of the equation

The answer is Yes

For (3, 1/4), we would substitute x = 3 and y = 1/4 into the equation. It becomes

5(3) + 4(1/4) = 15 + 1 = 16

Since 16 is not equal to 21, (3, 1/4) is not a solution