Answer:
In the equation, it divides 21 by x before knowing what x is, and gets it incorrect. Instead, you need to divide 21 by -4.2.
Step-by-step explanation:
-4.2x = 21
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-4.2
x = -5
You have to keep order of operations in mind.
1. Take care of the parentheses; distribute.
-3+6x-3=-20-8x
Simplified: 6x-6=-20-8x
2. Isolate the x variable.
Add 8x to both sides and add 6 to both sides.
14x=-14
3. Solve for x.
Divide by 14 on both sides.
x=-1
angles x y z are all acute because they are less than 90 degrees
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Answer:
The coordinates of the vertex is (6,4).
Step-by-step explanation:
The vertex is the highest or lowest point on the parabola (curved line).
Answer: She had 200 cards to start with
Step-by-step explanation:
Let x = the amount of cards she had initially. This means she had x cards to start with.
She gave half of the cards she had to a friend. This means she gave her friend x/2 cards. She is left with with (x-x/2) = x/2 cards.
She also gave 1/4 of the remaining cards to her brother. This means that she gave (1/4 × x/2) = x/8 cards to her brother.
Remaining number of cards will be x/2 - x/8 = (4x-x)/8 = 3x/8
She still has 75 cards left. This means
3x/8 = 75
Cross multiplying with 8, it becomes
3x = 75×8 = 600
x = 600/3 = 200
She had 200 cards to start with.