If u have 4\3 and 4\5 u add 4+4=8 and then do 5+3=8 and now you have 8\8 and that is how to add ixed fractions
You add two equations together to eliminate a variable. This particular problem is nice, because it's already setup to eliminate X.
3x - 4y = 9
<span>-3x + 2y = 9
</span>
When we add these two together, 3x - 3x cancels each other out, leaving us with 0x, or nothing.
We continue with -4y + 2y (leaves us with -2y) and 9+9 (18).
-2y = 18
18/-2 = -9.
Now we have y = -9, and we can go back into the problems to solve for x.
<span>3x - 4(-9) = 9
</span>
3x + 36 = 9.
3x = -27
x = -9.
Confirm with the final equation:
-3(-9) + 2(-9) = 9
27 - 18 = 9
9 = 9 --- Confirmed.
Answer:
Eric's expression is :

and Andrea's is :

In Eric's expression, 20 represents the initial amount of substance with which he has started the experiment.
is the amount of substance left after each time period (in this case, each week).The variable w in this case represents the number of weeks.
Andrea's expression can be written as :

The one outside of parentheses represents the initial amount of the substance. The one inside of parentheses represents 100% of the original amount of the substance. 0.5 represents the 50% of the substance that is lost each time period. The variable w in this case represents the number of weeks.
Answer:
Dimensions are 12 , 5
Step-by-step explanation:
Area of rectangular mural = length * width
length * width = 60 square feet
(x + 10)(x + 3) = 60
Use FOIL method
x*x + x*3 + 10*x + 10*3 = 60
x² + <u>3x + 10x</u> + 30 = 60 {Combine like terms}
x² +<u> 13x</u> + 30 - 60 = 0
x² + 13x - 30 = 0
Sum = 13
Product = -30
Factors = 15 , -2 (15+ (-2) = 13 ; 15*(-2) = -30)
x² + 15x - 2x - 30 =0 {Rewrite middle terms}
x(x + 15) - 2(x + 15) = 0
(x + 15)(x - 2) =0
x - 2 = 0 {Ignore (x +15) as dimensions wont have a negative value}
x = 2
x + 10 = 2 + 10 = 12
x + 3 = 2 + 3 = 5
Dimensions are 12 , 5
Answer:
Infinite solutions.
Step-by-step explanation:
If an equation is an identity, then there will be infinite solutions that the identity will have.
Let, us assume that an identity equation is given by
(a + b)² = a² +2ab + b².......... (1)
Now, putting any real values of a and b the identity will be satisfied.
Therefore, there are infinite solutions for an identity equation. (Answer)