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3t^2=2t-18, is a quadratic equation, need help to solve.

User James Tan
by
4.5k points

1 Answer

1 vote

Answer:

t = 1/3 + (i sqrt(53))/3 or t = 1/3 - (i sqrt(53))/3

Explanation:

Solve for t:

3 t^2 = 2 (t - 9)

Expand out terms of the right hand side:

3 t^2 = 2 t - 18

Subtract 2 t - 18 from both sides:

3 t^2 - 2 t + 18 = 0

Divide both sides by 3:

t^2 - (2 t)/3 + 6 = 0

Subtract 6 from both sides:

t^2 - (2 t)/3 = -6

Add 1/9 to both sides:

t^2 - (2 t)/3 + 1/9 = -53/9

Write the left hand side as a square:

(t - 1/3)^2 = -53/9

Take the square root of both sides:

t - 1/3 = (i sqrt(53))/3 or t - 1/3 = -(i sqrt(53))/3

Add 1/3 to both sides:

t = 1/3 + (i sqrt(53))/3 or t - 1/3 = -(i sqrt(53))/3

Add 1/3 to both sides:

Answer: t = 1/3 + (i sqrt(53))/3 or t = 1/3 - (i sqrt(53))/3

User Kavitha
by
4.4k points