## Mrather 2 years ago Which equation describes the four ordered pairs (-1,-3), (0,1), (2,9), (3,13)? A. y=2x+1 B. y=4x+1 C. y=4x-1 D. y=2x-1

1. sritama

B

2. incomplte

B

3. Callisto

Explanations?

4. sritama

put the values of x and y in the equations and find in which case 4 of them are satisfying the equation.

5. kirbykirby

Or there's a more systematic way of doing it:

6. kirbykirby

They give you the point (0,1) which is |dw:1358396550543:dw| your y-intercept in the formula y = mx+b, so b = 1 Now for the slope, take two points and calculate it using the slope formula: If we take points (-1,-3) and (0,1):$m=\frac{(-3)-(1)}{(-1)-(0)}= \frac{-4}{-1}=4$ So, y = 4x+1

7. kirbykirby

(And I guess you can assume the other points are valid for this equation since there is no option such as "none of the above")

8. kirbykirby

What sritama told you is perfectly valid as well, but perhaps a bit more time consuming