Answer:
how to solve 2x+2y=2 , -4x+4y=12
this is solving equations using substitution .... i have ALOT more but i juss dnt get this stuff
2x + 2y = 2 -4x + 4y = 12
x + y = 1
x = 1 - y
-4x + 4y = 12
-4(1 - y) + 4y = 12
(-4 + 4y) + 4y = 12
-4 + 8y = 12
8y = 16
y = 2
2x + 2y = 2
2x + 2(2) = 2
2x + 4 = 2
2x = -2
x = -1
Check.
-4x + 4y = 12
-4(-1) + 4(2) = 12
4 + 8 = 12
Answer: x = -1 and y = 2
Step-by-step explanation:
Answer/Step-by-step explanation:
1. The figure is composed of a triangle and a rectangle.
Area of the triangle = ½*base*height
base = 4 ft
height = 12 - 8 = 4ft
Area of triangle = ½*4*4 = 8 ft²
Area of rectangle = length * width
Length = 8 ft
Width = 4 ft
Area of rectangle = 8*4 = 32 ft²
✔️Area of the figure = 8 + 32 = 40 ft²
2. The figure is composed of a semicircle and a triangle
Area of the semicircle = ½(πr²)
radius (r) = 3 cm
π = 3
Area = ½(3*3²) = 13.5 cm²
Area of triangle = ½*base*height
base = 3*2 = 6 cm
height = 6 cm
Area = ½*6*6 = 6 cm²
✔️Area of the figure = 13.5 + 6 = 19.5 cm²
Complete question :
Mr. Nelson lost one of his students' test papers. He knows that the other 4 students scored as follows: 60, 62, 56, 57. He also knows that the average score is 59.2. What is the score on the missing paper?
Answer:
61
Step-by-step explanation:
Given the following :
Total number of students = 4 + 1 missing = 5
Score on the four avaliable papers = 60, 62, 56, 57
Average score of the 5 papers = 59.2
Score on missing paper :
Sum of each score / number of papers
Sum of each score = sum of available scores + missing score
Let missing score = m
(60 + 62 + 56 + 57 + m) = 235 + m
Recall:
Average = total sum / number of observations
Hence,
59.2 = (235 + m) / 5
59.2 × 5 = 235 + m
296 = 235 + m
m = 296 - 235
m = 61
Missing score = 61
Sarah has spent 7 first class tickets, and 6 coach tickets that totals for 13 people that took the trip.
$1040 * 7 = $7280
$140 * 6 = $840
$7280 + $840 = $8120 for Sarah's total budget she spent for 7 first class tickets and 6 coach tickets for 13 people that took the trip.
Answer:
7 first class tickets.
6 coach tickets.
Hope this helps!
<em>
</em><em>~ ShadowXReaper069</em>
The answer to this problem is -20