Given xy =4 and x^2 + y^2=a, which exspression is equal to (x+y)^2? a: a+6 b: a+4 c: a+8 d: a

Corretct answer is C: a+8

Step-by-step explanation:

Given xy=4 and x∧2+y∧2=a

The square of the binomial is

(x+y)∧2 = x∧2 + 2xy + y∧2  

when we rearrange this equation we get:

(x+y)∧2 = (x∧2 + y∧2) + 2 (xy) = a + 2 · 4 = a + 8

God with you!!!

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below:

hi,

i'm 75% sure the answer is 1,1 to both lines.

have a great day