HELP ME OUT PLEASE SOLVE IT..............

Question

Find a liner equation f(x) with slope 5 such that f(3)=12

Answer 1

Using f(x) the formula would be f(x) = 5x + b. The standard form of the slope intercept formula is

y = mx + b. The slope is represented by m, which equal 5. Since you know that f(3) = 12, the only unknown is b. So you simply plug in the known information and solve.

  y = mx + b

12 = 5(3) + b

12 = 15 + b

Subtract 15 from both sides.

b = -3

Prove the formula.

12 = 5(3) - 3

12 = 15 - 3

12 = 12

 

Answer 2

1. y = mx + b

 

2. (12) = (5)(3) + b

 

3. 12 = 15 + b

 

4. 12 - 15 = 15 + b - 15

 

5. -3 = b

 

y = 5x - 3

Answer 3

The slope intercept form of a straight line equation is

 

y = m x + b

 

where m = slope, b = y-intercept and y = f(x)

 

Plug in what is given to solve for unknown.

 

given x=3, f(3) = 12 = y, m=5

 

12 =  5(3) + b

solve for b

b = 12 - 15 = -3

 

The resulting linear equation using slope = 5 and b = -3 is

 

y = 5x - 3