Solve the simultaneous equations 4x+8y=-4 2y-5x=23

x = -4,  y = 3/2

Step-by-step explanation:

simplify the 1st equation by dividing each term by 4 to get:

x + 2y = -1

-5x + 2y = 23

Subtract to get: 6x = -24

x = -4

find 'y':    2y - 5(-4) = 23

               2y + 20 = 23

               2y = 3

                y = 3/2

y is equal to 1.5, and x is equal to -4

Step-by-step explanation:

given:

We can start by factoring 4 out of the first equation:

Now let's multiply it by -5:

We'll rearrange the other equation to match that (just for clarity):

Now let's subtract the modified equation from that:

So y is equal to 18/12, or 1.5

Let's plug that into one of the first equations and see what we get:

Giving us an x value of negative four.  Let's plug that into the other equation to confirm:

That matches up, so our answer is correct.

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.

answer: the answer is b. i think hope i got it correct

step-by-step explanation: