;7)h on the first line h65;2
Answer:
(C)
Step-by-step explanation:
Given the system of equations
From the first equation:
x+y=6
Making y the subject, we have:
y=-x+6
Substituting y=-x+6 into the second equation, we obtain:
<u>The correct option is C.</u>
NOTE: The goal of substitution is to reduce the number of unknown variables to 1. Therefore, after the substitution, if you still have the two unknown, you might have done something incorrect.
To find the product of (4x-5y)^2,
we can rewrite the problem as:
(4x-5y)(4x-5y) (two times because it is squared)
Now, time to use that old method we learned in middle school:
FOIL. (Firsts, Outers, Inners, and Lasts)
FOIL can help us greatly in this scenario.
Let's start by multiplying the 'Firsts' together:
4x * 4x = <em>16x^2</em>
Now, lets to the 'Outers':
4x * -5y = <em>-20xy</em>
Next, we can multiply the 'Inners':
-5y * 4x = <em>-20xy</em>
Finally, let's do the 'Lasts':
-5y * -5y = <em>25y</em>^2
Now, we can take the products of these equations from FOIL and combine like terms. We have: 16x^2, -20xy, -20xy, and 25y^2.
-20xy and -20xy make -40xy.
The final equation (product of (4x-5y)^2) is:
16x^2 - 40xy + 25y^2
Hope I helped! If any of my math is wrong, please report and let me know!
Have a good one.
I believe New York City was the first capital of the US.