MATHEMATICS MIDDLE SCHOOL

The line with equation ax+by=20 passes through the points(-2,10) and (1,5)
find a and b

Answers

Answer 1
Answer: ax+by=20 \n \n(-2,10) \n \n a*(-2)+b*10 = 20 \n \n-2a +10b = 20 \n \n (1,5)\n \n a*1+b*5 = 20 \n \n a +5b = 20
 
\begin{cases} -2a+10b =20\n a+5b =20 \ /*2\end{cases} \n \n\begin{cases} -2a+10b =20\n 2a+10b =40 \end{cases}\n--------\n 20b=60 \ / :20 \n \nb=(60)/(20) =3

-2a+10b=20 \n \n-2a +10*3=20 \n \n-2a +30=20\n \n-2a=20-30\n \n-2a=-10 \ /: (-2)

a=(10)/(2)=5\n \n\begin{cases} a= 5 \nb=3\end{cases}
Answer 2
Answer: ax+by=20\n\nfor\ (-2;\ 10)\to x=-2;\ y=10\ substitute\n\n-2a+10b=20\n\nfor\ (1;\ 5)\to x=1;\ y=5\ substitute\n\n1a+5b=20\n\n\n \left\{\begin{array}{ccc}-2a+10b=20&/:2\na+5b=20\end{array}\right
+\left\{\begin{array}{ccc}-a+5b=10\na+5b=20\end{array}\right\n------------\n.\ \ \ \ \ \ \ 10b=30\ \ \ \ /:10\n.\ \ \ \ \ \ \ \ b=3\n\n\left\{\begin{array}{ccc}b=3\na+5b=20\end{array}\right\n\left\{\begin{array}{ccc}b=3\na+5\cdot3=20\end{array}\right\n\left\{\begin{array}{ccc}b=3\na+15=20\end{array}\right\n\left\{\begin{array}{ccc}b=3\na=20-15\end{array}\right\n\left\{\begin{array}{ccc}b=3\na=5\end{array}\right


Answer:a=5\ and\ b=3\to5x+3y=20.

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Points V, W, X, Y, and Z are graphed on a number line. The coordinate of point V is –8. What points are at a distance of 5 units from point V?

Choose all answers that are correct.

A.
W = –13

B.
X = –8

C.
Y = –3

D.
Z = 3

Answers

Using the absolute value:
|x-(-8)|=5\n|x+8|=5\nx+8=5 \vee x+8=-5\nx=-3 \vee x=-13

A and C

What is 9/10 take away 4/5

Answers

Get a common denominator. 

9/10 
4/5 = 8/10

9/10 - 8/10 = 1/10

Answer: 1/10
9/10= .9 4/5= .8 .9-.8=.1.1 is the answer to nine tenths minus four fifths

If the price of a computer was decreased from $1,000 to $750, by what percent was the price decreased?

Answers

the answer is it got decreased by 25 percent 
it has got decreased by 25 percent.

Can someone please run the answer

Answers

1: =1/4; 0.3; 2/5; 0.65
2:=8 1/5; 8.44; 8.5; 8 4/5
3:=0.8888; 7/10; 3/5; 0.27
4:=8.04; 7 9/10; 7.85; 7 1/6
5:=5.8; 5 2/5; 4.33; 4 1/4
6:=1.2; 0.67; 5/8; 3/5
7:=9.3 and 9 1/4
8:= 8 1/3; 8.45; 8 9/10

YOUR WELCOME
Attached are pictures of the number lines for each problem. The easiest way to find fractions on a number line is to turn them into a decimal, which is done by dividing the top number by the bottom. For example, 3/5 would be 3 divided by 5.
Below are the numbers in order, least to greatest for #2, greatest to least for #3-6.

2. 8 1/5, 8.44, 8.5, 8 4/5
3. 0.888, 7/10, 3/5, 0.27
4. 8.04, 7 9/10, 7.85, 7 1/6
5. 5.8, 5 2/5, 4.33, 4 1/4
6. 1.2, 0.67, 5/8, 3/5

What is the average of 64 and 45?

Answers

Answer:

54.5

Step-by-step explanation:

you times the two numbers then divide by two

Answer: 54.4

Step-by-step explanation:

How to locate y axis and x axis

Answers

X is horizontal and Y is vertical.
X-axis is horizontal (or straight across) and the Y-acis is vertical (or up and down).
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24 + 0.44x = 19 + 1.69x