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3 years ago

Can someone please professionally explain the math equations below. (Not just answer the question)

Mathematics

1 answer:

Rus_ich [418]3 years ago

4 0

Step-by-step explanation:

We will solve this system of equations using two methods: elimination and substitution.

Method 1: Elimination

2x - y = -8. #1

-5x + y = 26. #2

Note that by adding these two equations, the y-variable is eliminated (thus the name) and you're only left with an equation with one variable. So upon adding, we get

-3x = 18 or x = -6

Using this value for x, put this back in either one of the equations. Let's use the 2nd one.

-5(-6) + y = 26

--> 30 + y = 26

Moving 30 to the right side, we get y = -4.

Method 2: Substitution

This is done by isolating one variable to the left side in one equation and then using it on the other equation. Let's take equation #2 and put the y-variable on the left side and you should get

y = 5x + 26

Now use this equation and plug it into the y in equation #1:

2x - (5x + 26) = -8

--> 2x - 5x - 26 = -8

--> -3x = 26 - 8 = 18 or x = -6.

Use this value for x into either one of the equations. Let's use equation #1 this time.

2(-6) - y = -8

--> -12 + 8 = y or y = -4.

Notice that using either method will give you the same result, as one might expect.

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rachel owns a cupcake shop. last week she used 42.5 pounds of sugar making cupcakes. this week she used 26 pounds of sugar. find

Paha777 [63]

Answer:

decreased by 39%

Step-by-step explanation:

deacreased by

42.5-26= 16.5

16.5÷42.5=38.82352941

rounded to 39%

3 0

3 years ago

Help how do you solve this (step by step preferably please) 7^x5^y7^z

Sophie [7]

Answer:

i realy try my best here it

Rewrite the equation as

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Step-by-step explanation:

7 0

2 years ago

Assuming the pattern continues, what are the next two terms in this

pshichka [43]

D. 53, 107
The pattern is multiplying the previous number by two and then adding one to it.

4 0

3 years ago

What is the unit rate for a 14 oz bag of Lays Potato Chips that costs $3.25.

Ronch [10]

The unit rate is 14 over 3.25 then get 1oz then divide by 3.25

4 0

3 years ago

Please help with this question.

barxatty [35]

Answer:

Step-by-step explanation:

The first thing we have to do is find the measure of angle A using the fact that the csc A = 2.5.

Csc is the inverse of sin. So we could rewrite as

$\frac{1}{sinA}=2.5$ or more easy to work with is this:

$\frac{1}{sinA} =\frac{2.5}{1}$

and cross multiply to get

2.5 sinA = 1 and

$sinA=\frac{1}{2.5}$ which simplifies to

sin A = .4

Using the 2nd and sin keys on your calculator, you'll get that the measure of angle A is 23.58 degrees.

We can find angle B now using the Triangle Angle-Sum Theorem that says that all the angles of a triangle have to add up to equal 180. Therefore,

angle B = 180 - 23.58 - 90 so

angle B = 66.42

The area of a triangle is

$A =\frac{1}{2}bh$ where h is the height of the triangle, namely side AC; and b is the base of the triangle, namely side BC. To find first the height, use the fact that angle B, the angle across from the height, is 66.42, and the hypotenuse is 3.9. Right triangle trig applies:

$sin(66.42)=\frac{h}{3.9}$ and

3.9 sin(66.42) = h so

h = 3.57

Now for the base. Use the fact that angle A, the angle across from the base, measures 23.58 degrees and the hypotenuse is 3.9. Right triangle trig again:

$sin(23.58)=\frac{b}{3.9}$ and

3.9 sin(23.58) = b so

b = 1.56

Now we can find the area:

$A=\frac{1}{2}(1.56)(3.57)$ so

A = 2.8 cm squared

3 0

3 years ago