Please help me, Evaluate [4 - (5 - 7(6 - 5) + 7)] + 4

3

Step-by-step explanation:

1st step:  (6-5) = 1; you now have:

[4 - 5 - 7(1) + 7)] + 4

2nd step:  7(1) = 7; you now have:

[4 - (5 - 7 + 7)] + 4

3rd step:  5 - 7 + 7 = 5; you now have:

[4 - 5] + 4, which is (-1 + 4) which equals 3

~

d. bc = 12 and ef = 16

step-by-step explanation:

we are given that δabc : δdef such that .

also, it is given that

so, from the options, we need that .

a.

b.

c.  

d.

as, we can see that only option d gives the same ratio as i.e. .

hence, the possible lengths are bc = 12 and ef = 16.