Answer:
Student B is correct
Student A failed to distribute -4 and -6 when opening the brackets in the first step
Step-by-step explanation:
The solution Student A gave was:
2x - 4(3x + 6) = -6(2x + 1) - 4
2x - 12x + 6 = -12x + 1 - 4
-10x + 6 = -12x - 3
2x = -9
x = -4 _1 2 ( -4 1/2)
The solution Student B gave was:
2x - 4(3x + 6) = -6(2x + 1) - 4
2x - 12x - 24 = -12x - 6 - 4
-10x - 24 = -12x - 10
2x = 14
x = 7
Student B is correct.
Explanation of the error:
Student A failed to distribute -4 and -6 when opening the brackets in the first step.
That is,
2x - 4(3x + 6) = -6(2x + 1) - 4
To open this bracket, we will distribute, -4 and -6 so that we get
2x (-4 × 3x) + (-4 × +6) = (-6×2x) + (-6 × +1) - 4
Then we will get
2x -12x -24 = -12x -6 -4
Adding the like terms
-10x - 24 = -12x - 10
Collecting like terms
-10x + 12x = -10 + 24
∴ 2x = 14
x = 14 / 2
Hence,
x = 7
Answer:
f(-3) = 16
Step-by-step explanation:
Given:
f(x) = 2x² + x + 1
Required:
f(-3)
Solution:
Substitute x = -3 into f(x) = 2x² + x + 1
f(-3) = 2(-3)² + (-3) + 1
f(-3) = 2*9 - 3 + 1
f(-3) = 18 - 3 + 1
f(-3) = 16
Answer:
zero
Step-by-step explanation:
If the same sum is received for the sale of 20 apples at price p as is received for the sale of 140 apples at price p, then we must have ...
20p = 140p
120p = 0 . . . . . . subtract 20p
p = 0 . . . . . . . . . divide by 120
The price was zero.
Answer: A. 3 x 3 x 3 x 4
Step-by-step explanation: 3 x 3 = 9 x 3 = 27 x 4 = 108
(1, M) this represents the miles per hour, which'll help find the other coordinates.
