Question

Graph the equation y=2x+3. Using the graph, find: For which value of x the value of y is equal to 1; 4; 0; −1

Answer 1

It is a linear function. We need only two points to plot the graph.

Choice any two values of x. Put them to the equation and calculate the values of y.

y = 2x + 3

for x = 2 → y = 2(2) + 3 = 4 + 3 = 7 → (2, 7)

for x = -2 → y= 2(-2) + 3 = -4 + 3 = -1 → (-2, -1)

Look at the picture.

Answer:

for x = -1 → y = 1

for x = 0 → y= 3

for x = 1 → y = 5

for x = 4 → y = 11