So you are multiplying the fractions together. You do not need a common denominator. You multiply the numerators together and the denominators to get your new fraction.
1x4=4
4x7=28
4/28
This fraction can now be simplified by dividing the numerator and denominator by 4
4/28x4/4
1/7
Answer:
Recall that a relation is an <em>equivalence relation</em> if and only if is symmetric, reflexive and transitive. In order to simplify the notation we will use A↔B when A is in relation with B.
<em>Reflexive: </em>We need to prove that A↔A. Let us write J for the identity matrix and recall that J is invertible. Notice that
. Thus, A↔A.
<em>Symmetric</em>: We need to prove that A↔B implies B↔A. As A↔B there exists an invertible matrix P such that
. In this equality we can perform a right multiplication by
and obtain
. Then, in the obtained equality we perform a left multiplication by P and get
. If we write
and
we have
. Thus, B↔A.
<em>Transitive</em>: We need to prove that A↔B and B↔C implies A↔C. From the fact A↔B we have
and from B↔C we have
. Now, if we substitute the last equality into the first one we get
.
Recall that if P and Q are invertible, then QP is invertible and
. So, if we denote R=QP we obtained that
. Hence, A↔C.
Therefore, the relation is an <em>equivalence relation</em>.
Answer: the option A.
The elimination method consist is adding the two equations in a way that one variable be eliminated..
In order to do that you might have to manipulate on of the equations prior to add the two equations.
In this case, ff you multiply the second equation by - 1 you will get
- x - y = - 4
which you can add to the first equation
2x + y = 8 to eliminate the y.
Answer:
77.1 feet
Step-by-step explanation:
<u>Scale model:</u>
Height = 18 inches
Width = 2.5 inches
<u>Actual monument:</u>
Height = 555 feet
Width = x feet
Write a proportion:

Answer:
x=10
y=30
Step-by-step explanation:
x=-2y+70
x=-2*3x+70
x=-6x+70
7x=70
x=10
y=3x
y=3*10
y=30