First subtract 4 from btoh sides of the equation
4 - 4 - 2x < 6-4
-2x < 2
Now divide both sides by -2
x > -1
NOTE: when dividing by a negative as above the inequality sign is flipped.
Answer:
-4/5
Step-by-step explanation:
Lets put the equation in slope intercept form
4x+5y = -20
Subtract 4x from each side
4x-4x+5y = -4x-20
5y = -4x-20
Divide each side by 5
5y/5 = -4x/5 -20/5
y = -4/5 x -4
The equation is in the form y = mx+b where m is the slope and b is the y intercept
the slope is -4/5 and the y intercept is -4
D is the answer to your question
Step-by-step explanation:
a2 = a1×r
a3 = a1×r²
a1×r + a1×r² = 6×a4 = 6×a1×r³
1.
r + r² = 6r³
6r³ - r² - r = 0
r×(6r² - r - 1) = 0
the first solution is obvious : r = 0.
but this is no useful ratio for a geometric sequence.
the other 2 solutions are in
6r² - r - 1 = 0
the general solutions for a quadratic equation are
(-b ± sqrt(b² - 4ac))/(2a)
in our case
a = 6
b = -1
c = -1
so,
(1 ± sqrt(1 - 4×6×-1))/12
r = (1 ± sqrt(25))/12
r = (1 ± 5)/12
r1 = (1+5)/12 = 6/12 = 1/2
r2 = (1-5)/12 = -4/12 = -1/3
2.
we can ignore r2 (negative) and just focus on r1 (1/2).
the second term is 8. that means
a2 = 8 = a1×r = a1×1/2
a1 = 2×a2 = 16
so, we have
a1 = 16
a2 = 8
a3 = a2×1/2 = 8×1/2 = 4
a4 = a3×1/2 = 4×1/2 = 2
a5 = a4×1/2 = 2×1/2 = 1
a6 = a5×1/2 = 1×1/2 = 1/2
a7 = a6×1/2 = 1/2 × 1/2 = 1/4