Question

How do you graph `3x-7y=21` using a table of values?

Answer 1

the straight line passes through two points (0, -3 ) and (7,0).

Explanation:

3x - 7y =21 is a linear simultaneous equation. For each value of x, there will be different value of y.
when x =o,
3 X 0 - 7 X y = 21
or, o - 7y = 21
or, -7y = 21
or -7y/-7 = 21/-7
or, y = -3
similarly for y = 0,
3x - 7 X0 = 21
or, 3x =21
or, 3x/3 = 21/3
or, x = 7
Hence the straight line passes through two points (0, -3 ) and (7,0).