Answer:
(14, -2)
Step-by-step explanation:
To solve by using substitution, begin by solving for a variable in the first equation. Let's solve for x:

Now we know what <em>x</em> equals. Let's substitute this into the second equation:

We can then simplify:
Given equation
Combine y terms
Add 2
Divide by -11
So, we now know the value of y = -2.
To find the value of X, we can substitute the value of Y into one of the equations. Let's use the first one:

Substitute for y
Distribute 8
Add 16
So, we now know the value of x = 14.
Therefore, we know a solution to the system of equations is (14, -2).
Answer:
13 pencils.
Step-by-step explanation:
Let x be the pens and y be the pencils
Given:
Brian purchased pens for 75 cents each and pencils for 40 cents each he bought total of 22 writing utensils for $11.95.
Total pens and pencils is 22
So,
----------------(1)
And he bought all utensils for $11.95. and each pen for 75 cents and pencils for 40 cents.
------------(2)
solve equation 1 and equation 2 for x and y.
From equation 1.

----------------(3)
put y value in equation 2.







Now substitute x value in equation 3.


So, he buy 13 pencils.
The absolute value of -3 is 3 and -3 so both would be right
<span>4. Simplify the expression.
sine of x to the second power minus one divided by cosine of negative x</span>
<span>(1−sin2(x))/(sin(x)−csc(x))<span>
</span>sin2x+cos2x=1</span>
<span>1−sin2x=cos2x<span>
</span>cos2(x)/(sin(x)−csc(x))</span>
<span>csc(x)=1/sin(x)</span>
<span>cos2(x)/(sin(x)− 1/sin(x))= cos2(x)/((sin2(x)− 1)/sin(x))</span>
<span>sin2(x)− 1=-cos2(x)</span>
<span>cos2(x)/(( -cos2(x))/sin(x))
=-sin(x)</span>
<span>
the answer is the letter a)
-sin x
</span><span>
5. Find all solutions in the interval [0, 2π). (6 points)sin2x + sin x = 0</span> using a graphical tool
the solutions
x1=0
x2=pi
<span>x3=3pi/2
the answer is the letter </span><span>
D) x = 0, π, three pi divided by two</span>