Substitute values into simple linear equations

Question 4

a		If y = 3x + 4, find y when x = 5
b		If P = 6T – 3, find P when T = 6

All of the equations here correspond to a straight-line graph. It takes only two points to determine a straight line.

We can find the coordinates of two points from the equation y = 3x + 4

When x = 0, y = 4. The coordinates are (0, 4)

When x = 2, y = 10. The coordinates are (2,10)

Straight line graph with positive gradient.

Detailed description of graph

Question 3

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