X=a-2by^2

Make “y” as a subject

Let’s assume a,b,x real. Then all we require of y is y2 is real, so y

can be real or purely imaginary, but not an arbitrary complex number.

The hard question in these is always, do we need ±

? Here the answer is yes. It’s basically asking is there one solution or two, and in this problem we have two.

Solve for y

: x=a−2by2

Step-by-step explanation:

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.

my answer is$ 12

step-by-step explanation:

because 15 -2=12