The solution of the simultaneous linear equations shown below is 2x - y=12 2x+y=13

(6.25, 0.5 )

Step-by-step explanation:

2x - y = 12 → (1)

2x + y = 13 → (2)

Add the 2 equations term by term to eliminate y

4x + 0 = 25

4x = 25 ( divide both sides by 4 )

x = 6.25

substitute x = 6.25 into either of the 2 equations and solve for y

substituting into (2)

2(6.25) + y = 13

12.5 + y = 13 ( subtract 12.5 from both sides )

y = 0.5

solution is (6.25, 0.5 )

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50