Question

4. In the exit slip, Brady got everything wrong. He needed to factor

x2 - 10x + 25 and 16x2 -9. This is his work.

x2 - 10x + 25 = x2 - 10x + 52

= x2 - 2(x)(5) + 52

= (x + 5)(x - 5)

16c2 – 9 = (40)2 – (3)2

= (40 - 3)2

Identify the error(s) in planning the solution or solving the problem. Write

the correct solution.

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of choice to

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Answer 1

Answer:

(1)The error is in third step.

The correct solution is (x-5)²

(2)The error is in third step.

The correct solution is (4c+3)(4c-c)

Step-by-step explanation:

(a-b) whole square is the sum square of a and b and subtraction of product of 2,a and b.

(a-b) = a²+b²-2ab

Therefore,

x²-10x+25

=x²-2.x.5+5²

=(x-5)²

The error is in third step.

The correct solution is (x-5)²

The subtraction of square of b from square a is the product of sum of a and b and the subtraction a from b.

(a²-b²)=(a+b)(a-b)

16c²-9

=(4c)²-3²

=(4c+3)(4c-c)

The error is in third step.

The correct solution is (4c+3)(4c-c)