Question

Daniel expanded the expression as shown. What errors did he make? Select three options.

-2(-8x-4y+3/4)=-10x-8y-1 1/4

A. The first term should be positive.

B. The second term should be positive.

C.The last term should be -1 1/2, not -1 1/4.

D. He divided -8 by -2 instead of multiplying -8 by -2.

E. He did not simplify the expression completely.

A, B, and C
Step-by-step explanation:
Let’s simply the equation first
• -2(-8 – 4y + 3/4)
• 16 + 8y – 1 1/2
What did Daniel do wrong?
Well, let’s break down what I did and compare it to Daniel.
• I multiplied -2 and -8x to get 16x. A negative number times a negative number is positive, and 2 times 8 is 16
Daniel, on the other hand, added the two terms.
The first term should be positive (A)
• I multiplied -2 and -4y to get 8y. The same sign rules apply.
Daniel got a negative number, but it is supposed to be positive (B)
• I multiplied -2 and 3/4 should be -6/4, which simplifies to -1 2/4 which is further reduced to -1 1/2
Daniel multiplied and simplified incorrectly (C)
-Chetan K