If an area of the rectangle below is 39 square feet, sides are x-2 and x+8 find the area of x

x  = 5.

Step-by-step explanation:

The area of a rectangle can be determined by the following formula.

A = l ⋅ w  

l  stands for length or the longer side.

w  stands for width or the shorter side.

Now, we can plug the values we are given into the equation.

A = ( x − 2 ) ⋅ ( x + 8 )

The easiest way to multiply is to follow the acronym FOIL , which stands for First Outside Inside Last, and dictates the order in which you multiply these terms.

A = x 2 + 8 x − 2 x −16 = x 2 + 6 x − 16

Now, we can plug in the given value for the area.

39 = x 2 + 6 x − 16  

Next, we simplify by moving all terms to one side and factor the equation.

0 = x 2 + 6 x − 55

Finally, we factor the equation. This means we reverse-FOIL, trying to determine the two things that we multiplied together.

0= ( x − 5 ) ⋅ ( x + 11 )

If the equation ultimately equals zero, either  ( x − 5 )  or  ( x + 11 )  or both equal zero. Therefore, we set each equal to zero to find the value of  

x .

x − 5 = 0 x = 5 x + 11 = 0

x = − 11

Since  x  is a length, we know it cannot be negative. Thus, we can conclude that it equals 5.

a.

step-by-step explanation:

step 1 distribute 2 to every term in the parentheses

step 2 add 10 on both sides of the equal sign

d) by the cross product property, ab^2 = bc multiplied by ad

step-by-step explanation:

we are given

in the given triangle abc

angle a is 90° and segment ad is perpendicular to segment bc

we can see that

triangle(abc) and triangle(abd) are similar because they have common side and same angle (90 degree)

so, triangles(abc) and abd are similar

since, they are similar

so, the ratio of their sides must be equal

we get

now, we can cross multiply

and we get

so, this could be step to prove it