<span>If you would like to know in which step did the student first make
an error, you can find this using the following steps:
y = 4 - 2z
4y = 2 - 4z
________________
-4(y) = -4(4 - 2z)
</span>4y = 2 - 4z<span>
________________
-4y = -16 + 8z ... Step 2
</span><span>4y = 2 - 4z</span><span>
________________
0 = -16 + 8z + 2 - 4z</span>
<span>16 - 2 = 4z</span>
<span>14 = 4z</span>
<span>z = 14/4 = 7/2</span>
<span>
The correct result would be: Student made an error in Step 2.</span>
Answer:
Discount = Original Price x Discount %/100
Discount = 37.99 × 80/100
Discount = 37.99 x 0.8
You save = $30.39
Final Price = Original Price - Discount
Final Price = 37.99 - 30.392
Final Price = $7.60
Answer:
B
Step-by-step explanation:
The vertex is always in the middle.
Answer:
x = 3 or -7
Step-by-step explanation:
Recall that for a quadratic equation in the form:
Ax² + Bx = C
we need to add (B/2)² to both sides of the equation to
In our case, we are given:
x² + 4x = 21
compared to the general equation above, B = 4, hence we need to add (4/2)² to both sides
x² + 4x = 21 (complete the square)
x² + 4x + (4/2)² = 21 + (4/2)²
x² + 4x + 2² = 21 + 2²
(x+ 2)² = 21 + 4
(x+ 2)² = 25 (take square root of both sides)
(x+2) = ±√25
(x+2) = ±5
hence
(x+2) = +5----> x = 5 - 2 = 3 (answer)
or
(x+2) = -5 ----> x = -5 - 2 = -7(answer)