Answer:

Step-by-step explanation:
For many of these identities, it is helpful to convert everything to sine and cosine, see what cancels, and then work to build out to something. If you have options that you're building toward, aim toward one of them.
and 
Recall the following reciprocal identity:

So, the original expression can be written in terms of only sines and cosines:





Working toward one of the answers provided, this is the tangent function.
The one caveat is that the original expression also was undefined for values of beta that caused the sine function to be zero, whereas this simplified function is only undefined for values of beta where the cosine is equal to zero. However, the questions states that we are only considering values for which the original expression is defined, so, excluding those values of beta, the original expression is equivalent to
.
Let :
T = Theresa age
H = her brother
We know :
T = H - 14
T + H = 35
Substitute T
H -14 + H = 35
2H - 14 = 35
2H = 49
H = 49/2 = 24.5
Since we know H = 24.5 we then can substitute it to either equation.
T = H - 14
T = 24.5 - 14
T = 10.5
Theresa is 10.5 years old
Her brother is 24.5 years old
The length of one of the legs of an isosceles right triangle and has a hypotenuse length of seven times the square root of two is 7 units.
<h3>What is an Isosceles triangle?</h3>
Isosceles triangles are triangles that has two of it sides equal to each other. The base angles of an isosceles triangle are equal.
The isosceles triangle is also a right angle triangle. The hypotenuse is the longest side of a right angle triangle.
Therefore,
hypotenuse = 7(√2)
let the length of the other legs = x
Therefore, using Pythagoras theorem
c² = a² + b²
(7(√2))² = x² + x²
49 × 2 = 2x²
98 = 2x²
x² = 98 / 2
x = √49
x = 7 units
learn more on isosceles triangle here: brainly.com/question/10412877
Exponentail thingies
easy, look at all them them, see that they have 5 in common?
rremember how esay it was to factor
ax^2+bx+c=0
now we have
5^(2x)-6(5^x)+5=0
remember that 5^(2x)=(5^2)^x or (5^x)^2
in other words, we can rewrite it as
1(5^x)^2-6(5^x)+5=0
if yo want, replace 5^x with a and factor
1a^2-6a+5=0
(a-1)(a-5)=0
a=5^x
(5^x-1)(5^x-5)=0
set each to zero
5^x-1=0
5^x=1
take the log₅ of both sides
x=log₅1
5^x-4=0
5^x=4
take the log₅ of both sides
x=log₅4
x=log₅1 and/or log₅4
second quesiton
same thing
1(2^x)-10(2^x)+16=0
factor
(2^x-8)(2^x-2)=0
set each to zero
2^x-8=9
2^x=8
x=3
2^x-2=0
2^x=2
x=1
x=3 or 1
first one
x=log₅1 and/or log₅4
second one
x=1 and/or 3
<u><em>Answer:</em></u>
y^2 = 28x
<em><u>Step-by-step explanation:</u></em>
Since the directrix is horizontal, use the equation of a parabola that opens left or right.
(y−k)^2 = 4p(x−h)
Find the vertex.
(0,0)
Find the distance from the focus to the vertex.
p = 7
Substitute in the known values for the variables into the equation
(y−k)^2 = 4p(x−h).
(y−0)^2 = 4(7)(x−0)
Simplify.
<em>y^2 = 28x</em>