Algebra 2

4 marks · Normal

Solve the equation for \( x \ ):

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x = 4 \text{ or } x = -4

Also accept: x=4, -4; x=-4, 4

Common mistakes: x=8; x=16

Show mark scheme and worked solution

Marking points

M1 · 1 mark · Subtracts 11 from both sides: LHS = 2x^2; RHS = 32

M2 · 1 mark · Divides both sides by 2 correctly. (follow-through)

M3 · 1 mark · Takes square root of both sides and recognizes sign. (follow-through)

A1 · 1 mark · Gives both values: and . (follow-through)

Worked solution

Subtract 11 from both sides:

Divide both sides by 2:

Take square roots: