Which statement is not true?

x2 = 100 if and only if x = 10 or x = –10.
if x2 = 100, then x = 10.
if x = –10, then x2 = 100.
if x = 10, then x2 = 100

Statement represented by option B is not a correct choice.

Step-by-step explanation:

We have been given 4 statements. We are asked to choose the statement that is not true.

A. , if and only if .

Let us solve for x by taking square root of both sides of our given equation.

Therefore, our given statement is true.

B. , then .

Upon taking square root we will get positive and negative 10, therefore, the given statement is false.

C. If , then  

Since we know that square of a negative number is positive, therefore, square of negative 10 is 100 and the given statement is true.

D. If , then  

Upon squaring 10 we will get 100, therefore, the given statement is true as well.

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

step-by-step explanation:

the true statements are:

r = set of real numbers

n = set of natural numbers, 1,2,

w = n u{0} = {0,1,}