Question
Simplify the expression
−x2+15x
Evaluate
(x−7)(x×7)−(x−8)(x×8)
Remove the parentheses
(x−7)x×7−(x−8)x×8
Multiply the terms
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Multiply the terms
(x−7)x×7
Use the commutative property to reorder the terms
(x−7)×7x
Multiply the terms
7x(x−7)
7x(x−7)−(x−8)x×8
Multiply the terms
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Multiply the terms
(x−8)x×8
Use the commutative property to reorder the terms
(x−8)×8x
Multiply the terms
8x(x−8)
7x(x−7)−8x(x−8)
Expand the expression
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Calculate
7x(x−7)
Apply the distributive property
7x×x−7x×7
Multiply the terms
7x2−7x×7
Multiply the numbers
7x2−49x
7x2−49x−8x(x−8)
Expand the expression
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Calculate
−8x(x−8)
Apply the distributive property
−8x×x−(−8x×8)
Multiply the terms
−8x2−(−8x×8)
Multiply the numbers
−8x2−(−64x)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
−8x2+64x
7x2−49x−8x2+64x
Subtract the terms
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Evaluate
7x2−8x2
Collect like terms by calculating the sum or difference of their coefficients
(7−8)x2
Subtract the numbers
−x2
−x2−49x+64x
Solution
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Evaluate
−49x+64x
Collect like terms by calculating the sum or difference of their coefficients
(−49+64)x
Add the numbers
15x
−x2+15x
Show Solution

Factor the expression
(−x+15)x
Evaluate
(x−7)(x×7)−(x−8)(x×8)
Remove the parentheses
(x−7)x×7−(x−8)x×8
Use the commutative property to reorder the terms
(x−7)×7x−(x−8)x×8
Multiply the terms
7x(x−7)−(x−8)x×8
Use the commutative property to reorder the terms
7x(x−7)−(x−8)×8x
Multiply the terms
7x(x−7)−8x(x−8)
Rewrite the expression
7(x−7)x−8(x−8)x
Factor out x from the expression
(7(x−7)−8(x−8))x
Solution
(−x+15)x
Show Solution

Find the roots
x1=0,x2=15
Evaluate
(x−7)(x×7)−(x−8)(x×8)
To find the roots of the expression,set the expression equal to 0
(x−7)(x×7)−(x−8)(x×8)=0
Use the commutative property to reorder the terms
(x−7)×7x−(x−8)(x×8)=0
Use the commutative property to reorder the terms
(x−7)×7x−(x−8)×8x=0
Multiply the terms
7x(x−7)−(x−8)×8x=0
Multiply the terms
7x(x−7)−8x(x−8)=0
Calculate
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Evaluate
7x(x−7)−8x(x−8)
Expand the expression
More Steps

Calculate
7x(x−7)
Apply the distributive property
7x×x−7x×7
Multiply the terms
7x2−7x×7
Multiply the numbers
7x2−49x
7x2−49x−8x(x−8)
Expand the expression
More Steps

Calculate
−8x(x−8)
Apply the distributive property
−8x×x−(−8x×8)
Multiply the terms
−8x2−(−8x×8)
Multiply the numbers
−8x2−(−64x)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
−8x2+64x
7x2−49x−8x2+64x
Subtract the terms
More Steps

Evaluate
7x2−8x2
Collect like terms by calculating the sum or difference of their coefficients
(7−8)x2
Subtract the numbers
−x2
−x2−49x+64x
Add the terms
More Steps

Evaluate
−49x+64x
Collect like terms by calculating the sum or difference of their coefficients
(−49+64)x
Add the numbers
15x
−x2+15x
−x2+15x=0
Factor the expression
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Evaluate
−x2+15x
Rewrite the expression
−x×x+x×15
Factor out −x from the expression
−x(x−15)
−x(x−15)=0
When the product of factors equals 0,at least one factor is 0
−x=0x−15=0
Solve the equation for x
x=0x−15=0
Solve the equation for x
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Evaluate
x−15=0
Move the constant to the right-hand side and change its sign
x=0+15
Removing 0 doesn't change the value,so remove it from the expression
x=15
x=0x=15
Solution
x1=0,x2=15
Show Solution
