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Solve.
9 + 7x = 7x^2

User NcRubert
by
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1 Answer

4 votes
Simplifying
9 + 7x = 7x2

Solving
9 + 7x = 7x2

Solving for variable 'x'.

Combine like terms: 7x2 + -7x2 = 0
9 + 7x + -7x2 = 0

Begin completing the square. Divide all terms by
-7 the coefficient of the squared term:

Divide each side by '-7'.
-1.285714286 + -1x + x2 = 0

Move the constant term to the right:

Add '1.285714286' to each side of the equation.
-1.285714286 + -1x + 1.285714286 + x2 = 0 + 1.285714286

Reorder the terms:
-1.285714286 + 1.285714286 + -1x + x2 = 0 + 1.285714286

Combine like terms: -1.285714286 + 1.285714286 = 0.000000000
0.000000000 + -1x + x2 = 0 + 1.285714286
-1x + x2 = 0 + 1.285714286

Combine like terms: 0 + 1.285714286 = 1.285714286
-1x + x2 = 1.285714286

The x term is -1x. Take half its coefficient (-0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
-1x + 0.25 + x2 = 1.
User Soumen Mukherjee
by
6.8k points