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Last problem had the wrong photo so heres the right one

Last problem had the wrong photo so heres the right one-example-1

1 Answer

7 votes

Answer:

J

Explanation:

1. y = mx + c ( equation of a straight line,where "c" is the y intercept, i.e, the y co-oridnate of where it cuts the y-axis)

2. It is now clear to see that the value of "c", the y co-ordinate of the point of intercept is 3, eliminating F and G as options

3. Substitute a given point into the equation y = mx + 3 to solve for "m", the gradient. I chose (3; 1) as it is the only visible point that lies on the straight line

4. Solve for "m" algebraically and you'll find that the gradient is -2/3

5. Substitute "m" back into the equation and you'll find that your equation is y = -2/3x + 3 or J

ALTERNATIVELY:

You could just find the value of "c" as stipulated above, which would leave you with H and J as options. But since you know the coefficient of x in the equation is the gradient, you can just tell by looking at the line whether or not it will have a positive or negative gradient. The gradient is negative since the line is sloping downwards, so you're only option is J.

User Krishna Shanbhag
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