Bricks are stacked according to the pattern shown below. Each row contains one more brick than the row above it.
Part A
Determine a quadratic function to model the total number of bricks in the stack,
f(x), given a number of rows, m.

Part A

The Quadratic Function to model the total number of bricks the stack is f(x) = x²

Part B

The number of bricks we will have for 50 rows is 2500 bricks

Step-by-step explanation:

Part A

Let the Quadratic Function to model the total number of bricks the stack, f(x), where x is the number of rows be f(x) = a·x² + b·x + c

We have;

When x = 0, f(x) = 0, therefore, f(0) = a×0² + b×0 + c = 0 + 0 + c = 0

∴ c = 0

When x = 1, f(x) = 1, therefore, f(1) = a×1² + b×1 + 0 = 1

∴ a + b = 1...(1)

When x = 2, f(x) = 4, therefore, f(2) = a×2² + b×2  = 4

∴ 4·a + 2·b = 4...(2)

Multiply equation (1) by 2, and subtract it from equation (2) gives;

4·a + 2·b - 2×(a + b) = 4 - 2 × 1

2·a = 2

a = 1

From equation (1), we have;

b = 1 - a = 1 - 1 = 0

b = 0

∴ f(x) = a·x² + b·x + c = 1·x² + 0·x + 0 = x²

Therefore, the Quadratic Function to model the total number of bricks the stack, f(x), where x is the number of rows be f(x) = x²

Part B

If there are 50 rows in the stack, then we have, x = 50

Therefore;

f(50) = 50² = 2500

The number of bricks we will have for 50 rows is f(50) = 2500 bricks

(just found it on )

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4

delaney would like to make a 5lb nut mixture that is 60% peanuts and 40% almonds.

she has several pounds of peanuts and several pounds of a mixture that is 20% peanuts and 80% almonds.

let 'p' represent the number of pounds of peanuts needed to make the new mixture, and  

let 'm' represent the number of pounds of the 80% almond-20% peanut mixture.

:

p + m = 5

therefore

m = (5-p)

write an equation based on the percent of peanuts

1p + .2m = .6(5)

replace m with (5-p)

p + .2(5-p) = .6(5)

p + 1 - .2p = 3

p - .2p = 3 - 1

.8p = 2

p = 2/.8

p = 2.5 lbs of peanuts required

then

5 - 2.5 = 2.5 lbs of the peanut/almond mixture required

:

a) what is the system that models this situation?

p + m = 5

1p + .2m = .6(5)