Question

The line passing through (4, a) and (8, 1) has gradient 0.75.
Work out the value of a.

Answer 1

Answer:

a = - 2

Step-by-step explanation:

calculate the slope of the 2 given points and equate to 0.75

m = $\frac{y_{2}-y_{1} }{x_{2}-x_{1} }$

with (x₁, y₁ ) = (4, a ) and (x₂, y₂ ) = (8, 1 )

m = $\frac{1-a}{8-4}$ = $\frac{1-a}{4}$

then equating

$\frac{1-a}{4}$ = 0.75 ( multiply both sides by 4 to clear the fraction )

1 - a = 3 ( subtract 1 from both sides )

- a = 2 ( multiply both sides by - 1 )

a = - 2