Sure! Let’s solve each problem step by step, combining like terms. “Like terms” are terms that have the
same variable(s) raised to the same power(s). We can only combine those.
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Part 1: Simplify each sum by combining like terms
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① (2a³ - 7a²) + (3a² + 3a³)
Step 1: Remove parentheses (since it’s addition, signs stay the same):
> 2a³ - 7a² + 3a² + 3a³
Step 2: Group like terms:
> (2a³ + 3a³) + (-7a² + 3a²)
Step 3: Combine coefficients:
> 5a³ - 4a²
✔ Answer: 5a³ - 4a²
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② (1 - 5a⁴) + (8a⁴ + 3)
Step 1: Remove parentheses:
> 1 - 5a⁴ + 8a⁴ + 3
Step 2: Group like terms:
> (-5a⁴ + 8a⁴) + (1 + 3)
Step 3: Combine:
> 3a⁴ + 4
✔ Answer: 3a⁴ + 4
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③ (-13k⁵ - 6 - 9k) + (3k⁵ + 8 + 8k)
Step 1: Remove parentheses:
> -13k⁵ - 6 - 9k + 3k⁵ + 8 + 8k
Step 2: Group like terms:
> (-13k⁵ + 3k⁵) + (-9k + 8k) + (-6 + 8)
Step 3: Combine:
> -10k⁵ - k + 2
✔ Answer: -10k⁵ - k + 2
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④ 6(4x² - 5x + 2) + 3(-8x² + 11x + 4)
Step 1: Distribute the numbers outside the parentheses:
> 6·4x² = 24x²
> 6·(-5x) = -30x
> 6·2 = 12
>
> 3·(-8x²) = -24x²
> 3·11x = 33x
> 3·4 = 12
So we get:
> 24x² - 30x + 12 - 24x² + 33x + 12
Step 2: Group like terms:
> (24x² - 24x²) + (-30x + 33x) + (12 + 12)
Step 3: Combine:
> 0x² + 3x + 24 →
3x + 24
✔ Answer: 3x + 24
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Part 2: Simplify each difference by combining like terms
*(Remember: subtracting a group means distributing the minus sign to every term inside!)*
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⑤ 4(6x³ - 4x² + 7x + 1) - 9(4x³ - 2x² - 6x + 1)
Step 1: Distribute both numbers:
> 4·6x³ = 24x³
> 4·(-4x²) = -16x²
> 4·7x = 28x
> 4·1 = 4
>
> -9·4x³ = -36x³
> -9·(-2x²) = +18x²
> -9·(-6x) = +54x
> -9·1 = -9
Now write all together:
> 24x³ - 16x² + 28x + 4 - 36x³ + 18x² + 54x - 9
Step 2: Group like terms:
> (24x³ - 36x³) + (-16x² + 18x²) + (28x + 54x) + (4 - 9)
Step 3: Combine:
> -12x³ + 2x² + 82x - 5
✔ Answer: -12x³ + 2x² + 82x - 5
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⑥ 10(4x² + 8x + 7) - 8(5x² + 10x - 9)
Step 1: Distribute:
> 10·4x² = 40x²
> 10·8x = 80x
> 10·7 = 70
>
> -8·5x² = -40x²
> -8·10x = -80x
> -8·(-9) = +72
So:
> 40x² + 80x + 70 - 40x² - 80x + 72
Step 2: Group like terms:
> (40x² - 40x²) + (80x - 80x) + (70 + 72)
Step 3: Combine:
> 0x² + 0x + 142 →
142
✔ Answer: 142
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⑦ 3(16x⁴ - 16x³ + 2x² - 8x + 24) - 4(8x⁴ - 12x³ - 2x² - 4x + 16)
Step 1: Distribute:
First part:
> 3·16x⁴ = 48x⁴
> 3·(-16x³) = -48x³
> 3·2x² = 6x²
> 3·(-8x) = -24x
> 3·24 = 72
Second part (remember to distribute the negative!):
> -4·8x⁴ = -32x⁴
> -4·(-12x³) = +48x³
> -4·(-2x²) = +8x²
> -4·(-4x) = +16x
> -4·16 = -64
Now put all together:
> 48x⁴ - 48x³ + 6x² - 24x + 72 - 32x⁴ + 48x³ + 8x² + 16x - 64
Step 2: Group like terms:
> (48x⁴ - 32x⁴) + (-48x³ + 48x³) + (6x² + 8x²) + (-24x + 16x) + (72 - 64)
Step 3: Combine:
> 16x⁴ + 0x³ + 14x² - 8x + 8
✔ Answer: 16x⁴ + 14x² - 8x + 8
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##
✔ Final Answers:
① 5a³ - 4a²
② 3a⁴ + 4
③ -10k⁵ - k + 2
④ 3x + 24
⑤ -12x³ + 2x² + 82x - 5
⑥ 142
⑦ 16x⁴ + 14x² - 8x + 8
Let me know if you’d like to see any step explained in more detail!
Parent Tip: Review the logic above to help your child master the concept of exponents and polynomials worksheet.