1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Charra [1.4K]
3 years ago
7

I DONT KNOW THESE! HELP!

Mathematics
1 answer:
kkurt [141]3 years ago
3 0

Answer:

20. x = 5, y = -2

21. x = 11, y = 12

22. x = 22, y = 11

23. x = 11, y = 10

Step-by-step explanation:

20. Opposite sides in the parallelogram are congruent, so

2y+18=3x-1\\ \\6x-3=17-5y

Solve this system of two equations:

\left\{\begin{array}{l}2y-3x=-19\\ \\6x+5y=20\end{array}\right.

Multiply the first equation by 2 and add two equations:

2(2y-3x)+6x+5y=2\cdot (-19)+20\\ \\4y-6x+6x+5y=-38+20\\ \\9y=-18\\ \\y=-2

Substitute it into the first equation:

2\cdot (-2)-3x=-19\\ \\-3x=-19+4\\ \\-3x=-15\\ \\x=5

21. Opposite angles in the parallelogram are congruent, so

11x+5=10y+6

Consecutive angles are supplementary, so

6x-y+11x+5=180^{\circ}

Solve this system of two equations:

\left\{\begin{array}{l}11x-10y=1\\ \\17x-y=175\end{array}\right.

From the second equation

y=17x-175

Substitute it into the first equation:

11x-10(17x-175)=1\\ \\11x-170x+1750=1\\ \\-159x=-1749\\ \\x=11\\ \\y=17\cdot 11-175=187-175=12

22. Opposite angles in the parallelogram are congruent, so

2x-5=3y-12

Consecutive angles are supplementary, so

2x-5+7y+x=180^{\circ}

Solve this system of two equations:

\left\{\begin{array}{l}2x-3y=-7\\ \\3x+7y=185\end{array}\right.

From the first equation

x=-3.5+1.5y

Substitute it into the second equation:

3(-3.5+1.5y)+7y=185\\ \\-10.5+4.5y+7y=185\\ \\-105+45y+70y=1,850\\ \\115y=1,850+105\\ \\115y=1,955\\ \\y=17\\ \\x=-3.5+1.5\cdot 17=22

23. Opposite sides in the parallelogram are congruent, so

2x+9=4y-9\\ \\3x-5=2y+8

Solve this system of two equations:

\left\{\begin{array}{l}2x-4y=-18\\ \\3x-2y=13\end{array}\right.

Multiply the second equation by 2 and subtract it from the first equation:

2x-4y-2(3x-2y)=-18-2\cdot 13\\ \\2x-4y-6x+4y=-18-26\\ \\-4x=-44\\ \\x=11

Substitute it into the first equation:

2\cdot 11-4y=-18\\ \\-4y=-18-22\\ \\-4y=-40\\ \\y=10

You might be interested in
(8.75-2.16)÷7.1+(4.5+1.3)÷4.3
kirill [66]

Answer:

2.27700622339

Step-by-step explanation:

Calculated your welcome

7 0
3 years ago
Read 2 more answers
Which shows the rational expression written using the least common denominator?x-2/x^3
Gelneren [198K]

Answer:

Multiply 2/3 and your number. If you have a whole number, convert it to a fraction by putting it over a denominator of 1. When multiplying fractions, calculate numerator times numerator, then denominator times denominator. For example, to find two-thirds of 18, multiply 2/3 x 18/1 to get 36/3.

6 0
3 years ago
Use properties to find the sum or product 93+(68+7)
Vlad [161]

Answer:

Step-by-step explanation:

93+(75)

= 168

3 0
3 years ago
What is the value of x? <br><br><br><img src="https://tex.z-dn.net/?f=%20%5Cfrac%7B4%7D%7B5%7D%20x%20-%20%20%5Cfrac%7B1%7D%7B10%
NeTakaya

Answer:

x = \frac{1}{2}

Step-by-step explanation:

Given

\frac{4}{5} x - \frac{1}{10} = \frac{3}{10}

Multiply through by 10 ( the LCM of 5 and 10 ) to clear the fractions

8x - 1 = 3 ( add 1 to both sides )

8x = 4 ( divide both sides by 8 )

x = \frac{4}{8} = \frac{1}{2}

6 0
3 years ago
7.) Find the Unit Rate: 32 flowers per 2 vases (flowers per vase)
IgorLugansk [536]

Answer:

16

Step-by-step explanation:

I JUST TOOK THE TEST YW

4 0
2 years ago
Other questions:
  • PLEASE HELP ASAP!!! 30 PTS
    7·1 answer
  • Eeeeeeeeeeaaaaaaddddddd
    10·1 answer
  • PLZ HELP ASAP INSCRIBED ANGLES
    11·1 answer
  • Determine whether the two triangles are similar. HELP ASAP! I AM RUNNING OUT OF POINTS!!
    11·1 answer
  • At the pet owner’s meeting, there are 20 people who own dog, and 35people who own cat and 9 people own goldfish. Some people own
    13·1 answer
  • If f(x)=2x-5, what is value of f(6)
    14·1 answer
  • Round 52.856 to the nearest hundreths
    6·2 answers
  • A bag has 11 red marbles and 4 yellow marbles. Half of the yellow marbles are made of plastic. A marble is selected at random fr
    9·2 answers
  • Rút gọn biểu thức <br> x^2-3/x+√3
    15·1 answer
  • Spiderman charges $25 for a service call plus $50 per hour of service. If Spiderman
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!