Ineed and i need to explain how i got it

y = (-1/8)x + 10.5

Step-by-step explanation:

The given equation is y = 8x -1.  The slope is 8.

Any line perpendicular to the given equation/line has a slope which is the negative reciprocal of 8:  That would be -1/8.

We'll use the point-slope formula of a straight line to come up with a formula for this specific problem:   y - k = m(x - h), where (h, k) is the point in question and m is the slope.

Here we have y - 10 = (-1/8)(x - 4).  This is complete in itself,  But you could also present it in more compact form, as follows:

Add 10 to both sides.  We get y = (-1/8)(x - 4) + 10.

Perform the indicated mult.:  y = (-1/8)x + 1/2 + 10, or

                                                y = (-1/8)x + 10.5

4sqrt5

step-by-step explanation:

the base has dimensions of 8 x 4, so the diagonal is 64 + 16 square rooted or 4sqrt5.

circle area = pi * radius^2

if diameter = 10 then radius = 5

circle area = pi * 5^2

circle area = pi * 25

circle area = 78.5398163397 square units

step-by-step explanation: