The line equation in slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept.
Write the two functions as co-ordinates.
First find the slope
(Substitute )
(Product of two same signs is positive)
(Subtract: )
(Add: 2 + 1 = 3)
(Divide: )
Next find the y-intercept
Substitute the slope and the coordinates of the given point in slope-intercept form equation.
y = mx + b
15 = –2(–2) + b (Substitute – 2 for m, – 2 for x, and 15 for y)
15 = 4 + b (Multiply: )
15 – 4 = 4 – 4 + b (Subtract 4 from each side)
15 – 4 = b (Apply additive inverse property: 4 – 4= 0)
b = 11 (Subtract: 15 – 4 = 11)
Finally write the line equation
Substitute the values of slope ‘m’ and y-intercept ‘b’ in slope intercept form line equation.
y = mx + b
y = –2(x) + 11 (Substitute –2 for m and 11 for b)
y = –2x + 11 (Simplify)
The function is y = –2x + 11.
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