algebra · worked example

Solve system: x+y=10 and x-y=4

Method: elimination. Verified step-by-step solution with our free AI math solver.
Problem

{x+y=10xy=4\begin{cases} x + y = 10 \\ x - y = 4 \end{cases}

Step-by-step solution

  1. Add the two equations to eliminate yy: (x+y)+(xy)=10+4(x+y) + (x-y) = 10 + 4, giving 2x=142x = 14.

  2. Solve: x=7x = 7.

  3. Substitute back into the first: 7+y=107 + y = 10, so y=3y = 3.

  4. Verify: 73=47 - 3 = 4 ✓.

Answer

(x,y)=(7,3)(x, y) = (7, 3)

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