1236inch (5191.2cm)
primeter of a triangle = sum of its threee sides
P.S. 1 inch=4.2 cm
Answer:
x = -2, y = -4
coordinate: (-2, -4)
Step-by-step explanation:
Given system of equations:
a) 4x - 7y = 20
b) x - 3y = 10
1. Make x the subject in the <em>second</em> equation:
⇒ x - 3y = 10 [add 3y to both sides]
⇒ x - 3y + 3y = 10 + 3y
⇒ x = 3y + 10
2. Substitute the given value of x into <em>first</em> equation:
⇒ 4x - 7y = 20
⇒ 4(3y + 10) - 7y = 20 [distribute 4 through the parentheses]
⇒12y + 40 - 7y = 20 [combine like terms]
⇒ 5y + 40 = 20 [subtract 40 from both sides]
⇒ 5y - 40 - 40 = 20 - 40
⇒ 5y = -20 [divide both sides by 5]
⇒ 5y ÷ 5 = -20 ÷ 5
⇒ y = -4
3. Find the value of x by substituting the given value of y into x = 3y + 10:
⇒ x = 3y + 10
⇒ x = 3(-4) + 10 [multiply]
⇒ x = -12 + 10 [add]
⇒ x = -2
4. Check your work:
<em>a) 4x - 7y = 20</em>
⇒ 4(-2) - 7(-4) = 20
⇒ -8 + 28 = 20
⇒ 20 = 20 ✔
<em>b) x - 3y = 10</em>
⇒ -2 - 3(-4) = 10
⇒ -2 + 12 = 10
⇒ 10 = 10 ✔
This system of equations has a solution at (-2, -4).
Learn more here:
brainly.com/question/27849342
brainly.com/question/27728118
“To use proportions to solve ratio word problems, we need to follow these steps:
Identify the known ratio and the unknown ratio.
Set up the proportion.
Cross-multiply and solve.
Check the answer by plugging the result into the unknown ratio.”
I hope this helps.
*dot plot is shown in the attachment below
Answer:
Mean = 6.3
Median = 6
Step-by-step explanation:
Measures of centre, mean and median, can be calculated as follows:
First, bear in mind that each dot represents a value in the data set.
==>Mean:
Mean is the sum of all values in the data set divided by the number of data set we have.
The sum can be calculated as follows:
0 (1) = 0
4 (3) = 12
5(8) = 40
6(3) = 18
7(1) = 7
8(5) = 40
9(2) = 18
10 (3) = 30
Sum = 0+12+40+18+7+40+18+30 = 165
No of data set = 26
Mean = 165/26 = 6.346 ≈ 6.3 (nearest tenth place)
==>Median: this is the middle value in the data set. Since the number of data set is even number (26) , the middle value lies between the 13th and 14th data points. The average of the 13th and 14th data points will give us the median value.
Thus, the 13th and 14th values are both 6.
Therefore, median = (6+6) ÷ 2 = 6
