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If BC=2x-3 and AC=2x+10, find the length of AB

User Oyvindhauge
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1 Answer

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Final answer:

To find the length of AB, use the Pythagorean theorem and solve for x. Then substitute the value of x back into the equation to find the length of AB.

Step-by-step explanation:

To find the length of AB, we can use the concept of the Pythagorean theorem. The Pythagorean theorem states that in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides. In this case, AB is the hypotenuse of a right triangle with sides BC and AC. So, we can set up the equation:

AB^2 = BC^2 + AC^2

Substituting the given values:

(2x-3)^2 = (2x-3)^2 + (2x+10)^2

Expanding and simplifying the equation:

4x^2 - 12x + 9 = 4x^2 - 24x + 9 + 4x^2 + 40x + 100

Combining like terms:

-12x = -24x + 40x + 100 - 9

Simplifying the equation further:

-12x = 16x + 91

Bringing all the x terms to one side:

14x = -91

Dividing both sides by 14:

x = -91/14

Substituting the value of x back into AB:

AB = 2(-91/14) - 3

Simplifying the equation:

AB = -182/14 - 3

AB = -13.14 cm

User Seamus Campbell
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