1.) Solve for x:
5 x + 7 = 3 x + 21
Subtract 3 x from both sides:
(5 x - 3 x) + 7 = (3 x - 3 x) + 21
5 x - 3 x = 2 x:
2 x + 7 = (3 x - 3 x) + 21
3 x - 3 x = 0:
2 x + 7 = 21
Subtract 7 from both sides:
2 x + (7 - 7) = 21 - 7
7 - 7 = 0:
2 x = 21 - 7
21 - 7 = 14:
2 x = 14
Divide both sides of 2 x = 14 by 2:
(2 x)/2 = 14/2
2/2 = 1:
x = 14/2
The gcd of 14 and 2 is 2, so 14/2 = (2×7)/(2×1) = 2/2×7 = 7:
Answer: x = 7
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2.) Solve for x:
3 x - 2 (5 - x) = 3 x - 3 (x - 10)
-2 (5 - x) = 2 x - 10:
2 x - 10 + 3 x = 3 x - 3 (x - 10)
Grouping like terms, 3 x + 2 x - 10 = (3 x + 2 x) - 10:
(3 x + 2 x) - 10 = 3 x - 3 (x - 10)
3 x + 2 x = 5 x:
5 x - 10 = 3 x - 3 (x - 10)
-3 (x - 10) = 30 - 3 x:
5 x - 10 = 30 - 3 x + 3 x
3 x - 3 x = 0:
5 x - 10 = 30
Add 10 to both sides:
5 x + (10 - 10) = 10 + 30
10 - 10 = 0:
5 x = 30 + 10
30 + 10 = 40:
5 x = 40
Divide both sides of 5 x = 40 by 5:
(5 x)/5 = 40/5
5/5 = 1:
x = 40/5
The gcd of 40 and 5 is 5, so 40/5 = (5×8)/(5×1) = 5/5×8 = 8:
<span>Answer: x = 8
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3.) Solve for x:</span>
5 (x + 1) = 3 (2 x + 3) + 5
3 (2 x + 3) = 6 x + 9:
5 (x + 1) = 6 x + 9 + 5
Grouping like terms, 6 x + 5 + 9 = 6 x + (9 + 5):
5 (x + 1) = 6 x + (9 + 5)
9 + 5 = 14:
5 (x + 1) = 6 x + 14
Expand out terms of the left hand side:
5 x + 5 = 6 x + 14
Subtract 6 x from both sides:
(5 x - 6 x) + 5 = (6 x - 6 x) + 14
5 x - 6 x = -x:
-x + 5 = (6 x - 6 x) + 14
6 x - 6 x = 0:
5 - x = 14
Subtract 5 from both sides:
(5 - 5) - x = 14 - 5
5 - 5 = 0:
-x = 14 - 5
14 - 5 = 9:
-x = 9
Multiply both sides of -x = 9 by -1:
(-x)/(-1) = -9
(-1)/(-1) = 1:
<span>Answer: x = -9</span>
Answer:
a = 76 b = 22 c = 58 d = 68
Step-by-step explanation:
A. 180 - 133 = 47
so you have two angles found, which is 57 and 47. Add them together and subtract from 180. You get 76
B. 68 + 90 = 158
You subtract the 158 from 180 and get 22
C. This took some guess work, but when you multiply 58 by 2 you get 116. When subtracted from 180 you get 64. If you add 58 + 58 + 64, you get 180, so this made sense
D. There's an actual rule in trig that explains this, but I forgot it. If you look at the top angle, the other side of the line added to the 68 is a right angle. So you subtract 68 from 90 and get 12. Because there is already the right angle in the triangle, you just need the other two angles to equal 90, and because of the 68 that we found in the other triangle, this made sense.
Sorry, not the best at explanations. Hope that helped
Answer:
(8, 5) (Answer C)
Step-by-step explanation:
Write this system of linear equations in a (vertical) column:
4x - 3y = 17
5x + 4y = 60
Let's eliminate y through addition/subtraction:
Multiply 4x - 3y = 17 by 4, obtaining 16x - 12y = 68, and
multiply 5x + 4y = 60 by 3, obtaining 15x + 12y = 180. Then we have:
16x - 12y = 68
15x + 12y = 180
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31x = 248, and so x = 248/31 = 8.
Now find y. Substitute 8 for x in 5x + 4y = 60: 5(8) + 4y = 60, or
4y = 60 - 40 = 20.
Thus, y = 20/4, or y = 5.
The solution is (8, 5) (Answer C)
Answer:
66
Step-by-step explanation:
11 times 6 = 66
16 oz because if you do 48/16 you get 3 and 4 times $4.87 equals less then 13.97
