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2 years ago

I need help? With proof for this one.

Mathematics

1 answer:

Schach [20]2 years ago

3 0

Answer:

See below.

Step-by-step explanation:

ABC is an isosceles triangle with BA = BC.

That makes angles A and C congruent.

ABD is an isosceles triangle with AB = AD.

That makes angles ABD and ADB congruent.

Since m<ABD = 72 deg, then m<ADB = 72 deg.

Angles ADB and CDB are a linear pair which makes them supplementary.

m<ADB + m<BDC = 180 deg

72 deg + m<BDC = 180 deg

m<CDB = 108 deg

In triangle ABD, the sum of the measures of the angles is 180 deg.

m<A + m<ADB + m<ABD = 180 deg

m<A + 72 deg + 72 deg = 180 deg

m<A = 36 deg

m<C = 36 deg

In triangle BCD, the sum of the measures of the angles is 180 deg.

m<CBD + m<C + m<BDC = 180 deg

m<CBD + 36 deg + 108 deg = 180 deg

m<CBD = 36 deg

In triangle CBD, angles C and CBD measure 36 deg making them congruent.

Opposite sides DB and DC are congruent making triangle BCD isosceles.

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A homeowner has 32 feet of fencing to build three sides of a rectangular chicken coup. One side of the chicken coup will be agai

zepelin [54]

Answer:

The ideal length is 16 feet

The ideal width is 8 feet

Step-by-step explanation:

The given parameters are;

The length of the fencing available to the homeowner = 32 feet

The number of sides of the rectangular chicken coup the fence will be applied = 3 sides

Let L represent the length and W, represent the width

Therefore, we have;

The perimeter of the fence = 2W + L = 32 feet

L = 32 - 2·W

The area is given by, A = Length, L × Width, W

A = (32 - 2·W) × W = 32·W - 2·W²

Differentiating with respect to W and equating to 0 to find the maximum point gives;

dA/dW = d(32·W - 2·W²)/dW = 0

32 - 4·W = 0

4·W = 32

W = 32/4 = 8

W = 8 feet

Given that the sign of the variable in the equation of the derivative is negative, the value we get is the maximum point

The ideal width W = 8 feet

The length, L = 32 - 2·W = 32 - 2 × 8 = 16 feet

Therefore, the ideal length, L = 16 feet.

6 0

2 years ago

Use the substitution method to solve the system of equations.

Murrr4er [49]

Answer:

D. (1/4, -2)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Equality Properties

Algebra I

Solving systems of equations using substitution/elimination

Step-by-step explanation:

Step 1: Define Systems

y = -8x

4x - y = 3

Step 2: Solve for x

Substitution

Substitute in y: 4x - (-8x) = 3
Simplify: 4x + 8x = 3
Combine like terms: 12x = 3
Isolate x: x = 3/12
Simplify: x = 1/4

Step 3: Solve for y

Define equation: y = -8x
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2 years ago

Ms. Brown's class is learning about banks, so she creates one in her classroom. All students start with $75 in their accounts. L

Katen [24]

Answer:

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Step-by-step explanation:

4 0

2 years ago

Question 1

12345 [234]

Answer:

A). Surface area = 222 cm²

Volume = 180 cm³

B). Surface area = 375 cm²

Volume = 360 cm³

C). % increase in surface area = 67.57%

% increase in volume = 100%

Step-by-step explanation:

In the figure attached base of a prism has been given.

A). Surface area of the prism = (Perimeter of the base of the prism) × height + 2(area of the base)

Perimeter of the base = 5 + 3 + 2 + 2 + 2 + 3 + 5 + 8

= 30

Area of the base = 8×5 - 2×2 = 36 cm²

Surface area of the prism = 30×5 + 2×(36)= 222 cm²

Volume of the prism = volume of the bigger prism - volume of the smaller prism cut off

= 8×5×5 - 2×2×5

= 200 - 20

= 180 cm³

B). Surface area of the prism if it's height is 10 cm,

Surface area = 30×10 + 2×(36) = 372 cm²

Volume of the prism = 8×5×10 - 2×2×10

= 400 - 40

= 360 cm³

C). Increase in surface area = 372 - 222 = 150 cm²

% increase in the surface area = $\frac{150}{222}\times 100$ = 67.57%

Increase in volume = 360 - 180 = 180 cm³

% increase in volume = $\frac{180}{180}\times 100$ = 100%

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2 years ago

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kykrilka [37]

Answer:

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2 years ago