3rd one. The circle is on 7 and is going to the left.
Answer:
3(x-2)+x=4x+6
Step-by-step explanation:
case 1) we have
3(x-2)+x=4x-6
Solve for x
3x-6+x=4x-6
4x-6=4x-6
0=0 ----> is true for any value of x
therefore
The equation has infinite solutions
case 2) we have
3(x-2)+x=2x-6
3x-6+x=2x-6
4x-2x=-6+6
2x=0
x=0
case 3) we have
3(x-2)+x=3x-3
3x-6+x=3x-3
4x-3x=-3+6
x=3
case 4) we have
3(x-2)+x=4x+6
3x-6+x=4x+6
4x-4x=6+6
0=12 ------> is not true
therefore
The equation has no solution
Let's turn 3 hours and 3 minutes into minutes.
One hour=60×3=180+3=183
So, there's 183 minutes in 3 hours and 3 minutes. We need to divide 26.2 miles by 183.
26.2÷183≈ 0.143
So, Sally ran 0.143 miles every minute.
Answer:
D
Step-by-step explanation:
Let's substitute a for x²:
x^4 - 3x² - 4
a² - 3a - 4
Now, this looks like something that is much more factorisable:
a² - 3a - 4 = (a - 4)(a + 1)
Plug x² back in for a:
(a - 4)(a + 1)
(x² - 4)(x² + 1)
The first one is a difference of squares, which can be factored into:
x² - 4 = (x + 2)(x - 2)
The second one can also be treated as a difference of squares:
x² + 1 = x² - (-1) = (x + √-1)(x - √-1) = (x + i)(x - i)
The answer is (x + 2)(x - 2)(x + i)(x - i), or D.