Answer:
21440
Step-by-step explanation:
<h2>
Simplify:</h2>
Start by multiplying 7x³ by x² and -5.
- 7x⁵ - 35x³ + (8x² - 3)(x² - 5)
Multiply 8x² by x² and -5.
- 7x⁵ - 35x³ + 8x⁴ - 40x² + (-3)(x² - 5)
Multiply -3 by x² and -5.
- 7x⁵ - 35x³ + 8x⁴ - 40x² -3x² + 15
Combine like terms together.
- 7x⁵ - 35x³ + 8x⁴ - 43x² + 15
Rearrange the terms in descending power order.
- 7x⁵ + 8x⁴ - 35x³ - 43x² + 15
<h2>Verify (I): </h2>
Substitute x = 5 into the above polynomial.
- 7(5)⁵ + 8(5)⁴ - 35(5)³ - 43(5)² + 15
Evaluate the exponents first.
- 7(3125) + 8(625) - 35(125) - 43(25) + 15
Multiply the terms together.
- 21875 + 5000 - 4375 - 1075 + 15
Combine the terms together.
This is the answer when substituting x = 5 into the simplified expression.
<h2>
Verify (II):</h2>
Substitute x = 5 into the expression.
- [7(5)³ + 8(5)² - 3][(5)² - 5]
Evaluate the exponents first.
- [7(125) + 8(25) - 3][(25) - 5]
Multiply the terms in the first bracket next.
Evaluate the expressions inside the brackets.
Multiply these two terms together.
This is the answer when substituting x = 5 into the original (unsimplified) expression.
Answer: 50
Step-by-step explanation: If a dozen is 3 pounds then half a dozen would 6 which should be 1.50 lb. Now we need to know how much 1 banana weights. lets add all twelve until we have 3 pounds. 12 x 25 = 300 or 3.00 lb so we now know 2 bananas weight 50.
Answer:
<h2>1 < x < 6 ⇒ x ∈ (1, 6)</h2>
Step-by-step explanation:
3x - 8 > -5 <em>add 8 to both sides</em>
3x > 3 <em>divide both sides by 3</em>
x > 1
2x - 7 < 5 <em>add 7 to both sides</em>
2x < 12 <em>divide both sides by 2</em>
x < 6
From x > 1 and x < 6 we have the solution 1 < x < 6 ⇒ x ∈ (1, 6)
D. About 122 units I just took the test
Answer:
∠AEC = 139°
Step-by-step explanation:
Since EC bisects ∠BED then ∠BEC = ∠CED = 4x + 1
∠AED = ∠AEB + ∠BEC + ∠CED = 180 ← straight angle
Substitute values into the equation
11x - 12 + 4x + 1 + 4x + 1 = 180, that is
19x - 10 = 180 ( add 10 to both sides )
19x = 190 ( divide both sides by 19 )
x = 10
Hence
∠AEC = ∠AEB + ∠BEC = 11x - 12 + 4x + 1 = 15x - 11, hence
∠AEC = (15 × 10) - 11 = 150 - 11 = 139°