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2 years ago

A student performed the following steps to find the solution to the question x^2 - 2x - 15 = 0. Where did the student go wrong?

Mathematics

1 answer:

nataly862011 [7]2 years ago

7 0

Answer:

D In step 3

Step-by-step explanation:

Given polynomial: x² - 2x - 15 = 0

Step 1: factor the polynomial ⇒ (x + 3)(x - 5) = 0

Step 2: x + 3 = 0 and x - 5 = 0

Step 3: x = -3 and x = 5

x - 5 = 0

Add 5 to both sides:

⇒ x - 5 + 5 = 0 + 5

⇒ x = 5

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3 years ago

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Answer:

Coordinates of X is (7/2,9/2)

Coordinates of C is (6,7)

Explanation:

x is the midpint of DB and AC

coordinates of X = ( (5+2)/2 ,(6+3)/2)

= (7/2,9/2)

Coordinates of X is (7/2,9/2)

Let (a,b) be the coordinates of C.

Then,

coordinates of x = ((a+1)/2, (b+2)/2)

(7/2,9/2) = ((a+1)/2, (b+2)/2)

Hence,

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9 =b+2

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