Question

Does anyone know the answer to this question?

Answer 1

c = 2.5

d = - 3

Explanation:

f(x) = cx + d

f(4) = 7

f(10) = 22

4c + d = 7

10c + d = 22

(10c - 4c) + (d - d) = 22 - 7

6c = 15

--- ----

6 6

c = 2.5

4(2.5) + d = 7

10 + d = 7

-10 -10

d = - 3

Answer 2

c = 2.5 , d = - 3

Explanation:

f(x) = cx + d

f(4) = 7 ( substitute x = 4 into the equation and equate to 7 )

f(10) = 22 ( substitute x = 10 into the equation and equate to 22 )

4c + d = 7 → (1)

10c + d = 22 → (2)

subtract (1) from (2) term by term to eliminate d

(10c - 4c) + (d - d) = 22 - 7 , that is

6c = 15 ( divide both sides by 6 )

c = 2.5

substitute c = 2.5 into (1) and solve for d

4(2.5) + d = 7

10 + d = 7 ( subtract 10 from both sides )

d = - 3