Question
Solve the system of equations
(x1,y1)=(2887+721,67−721)(x2,y2)=(2887−721,67+721)
Evaluate
{2x×9y=−144x−3y−144x−3y=−7
Calculate
{18xy=−144x−3y−144x−3y=−7
Solve the equation for x
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Evaluate
−144x−3y=−7
Move the expression to the right-hand side and change its sign
−144x=−7+3y
Change the signs on both sides of the equation
144x=7−3y
Divide both sides
144144x=1447−3y
Divide the numbers
x=1447−3y
{18xy=−144x−3yx=1447−3y
Substitute the given value of x into the equation 18xy=−144x−3y
18×1447−3y×y=−144×1447−3y−3y
Simplify
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Evaluate
18×1447−3y×y
Multiply the terms
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Multiply the terms
18×1447−3y
Cancel out the common factor 18
1×87−3y
Multiply the terms
87−3y
87−3y×y
Multiply the terms
8(7−3y)y
Multiply the terms
8y(7−3y)
8y(7−3y)=−144×1447−3y−3y
Simplify
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Evaluate
−144×1447−3y−3y
Multiply the terms
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Multiply the terms
−144×1447−3y
Cancel out the common factor 144
−1×(7−3y)
Multiply the terms
−(7−3y)
Calculate
−7+3y
−7+3y−3y
The sum of two opposites equals 0
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Evaluate
3y−3y
Collect like terms
(3−3)y
Add the coefficients
0×y
Calculate
0
−7+0
Remove 0
−7
8y(7−3y)=−7
Cross multiply
y(7−3y)=8(−7)
Simplify the equation
y(7−3y)=−56
Expand the expression
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Evaluate
y(7−3y)
Apply the distributive property
y×7−y×3y
Use the commutative property to reorder the terms
7y−y×3y
Multiply the terms
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Evaluate
y×3y
Use the commutative property to reorder the terms
3y×y
Multiply the terms
3y2
7y−3y2
7y−3y2=−56
Move the expression to the left side
7y−3y2−(−56)=0
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
7y−3y2+56=0
Rewrite in standard form
−3y2+7y+56=0
Multiply both sides
3y2−7y−56=0
Substitute a=3,b=−7 and c=−56 into the quadratic formula y=2a−b±b2−4ac
y=2×37±(−7)2−4×3(−56)
Simplify the expression
y=67±(−7)2−4×3(−56)
Simplify the expression
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Evaluate
(−7)2−4×3(−56)
Multiply
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Multiply the terms
4×3(−56)
Rewrite the expression
−4×3×56
Multiply the terms
−672
(−7)2−(−672)
Rewrite the expression
72−(−672)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
72+672
Evaluate the power
49+672
Add the numbers
721
y=67±721
Separate the equation into 2 possible cases
y=67+721y=67−721
Evaluate the logic
y=67+721∪y=67−721
Rearrange the terms
{x=1447−3yy=67+721∪{x=1447−3yy=67−721
Calculate
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Evaluate
{x=1447−3yy=67+721
Substitute the given value of y into the equation x=1447−3y
x=1447−3×67+721
Calculate
x=2887−721
Calculate
{x=2887−721y=67+721
{x=2887−721y=67+721∪{x=1447−3yy=67−721
Calculate
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Evaluate
{x=1447−3yy=67−721
Substitute the given value of y into the equation x=1447−3y
x=1447−3×67−721
Calculate
x=2887+721
Calculate
{x=2887+721y=67−721
{x=2887−721y=67+721∪{x=2887+721y=67−721
Calculate
{x=2887+721y=67−721∪{x=2887−721y=67+721
Check the solution
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Check the solution
{2×2887+721×9×67−721=−144×2887+721−3×67−721−144×2887+721−3×67−721=−7
Simplify
{−7=−7−7=−7
Evaluate
true
{x=2887+721y=67−721∪{x=2887−721y=67+721
Check the solution
More Steps

Check the solution
{2×2887−721×9×67+721=−144×2887−721−3×67+721−144×2887−721−3×67+721=−7
Simplify
{−7=−7−7=−7
Evaluate
true
{x=2887+721y=67−721∪{x=2887−721y=67+721
Solution
(x1,y1)=(2887+721,67−721)(x2,y2)=(2887−721,67+721)
Show Solution
