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Need help on this please​

Need help on this please​-example-1
User Takehiro Iyatomi
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1 Answer

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19 votes

Explanation:

the slope-intercept form is

y = ax + b

"a" is the slope (the slope is in all forms the factor of x). and "b" is the y-intercept (the y value when x = 0).

so the first equation is

y = -5x + b

b we get by using the point coordinates :

-22 = -5×5 + b = -25 + b

b = 3

so, the full equation is

y = -5x + 3

for the second equation we need to calculate the slope first. remember, it is the ratio "y coordinate change / x coordinate change" :

x changes by +1 (from -4 to -3).

y changes by +7 (from -2 to 5).

the slope is +7/+1 = 7/1 = 7.

the equation looks like

y = 7x + b

again, we use the coordinates of a point to get b. I picked (-4, -2) :

-2 = 7×-4 + b = -28 + b

b = 26

and the full equation is

y = 7x + 26

User Brian Li
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2.9k points