Answer:
x = 3
Step-by-step explanation:
2x + 8 = 14
2x = 6
x = 3
Answer:
To prove that 3·4ⁿ + 51 is divisible by 3 and 9, we have;
3·4ⁿ is divisible by 3 and 51 is divisible by 3
Where we have;
= 3·4ⁿ + 51
= 3·4ⁿ⁺¹ + 51
-
= 3·4ⁿ⁺¹ + 51 - (3·4ⁿ + 51) = 3·4ⁿ⁺¹ - 3·4ⁿ
-
= 3( 4ⁿ⁺¹ - 4ⁿ) = 3×4ⁿ×(4 - 1) = 9×4ⁿ
∴
-
is divisible by 9
Given that we have for S₀ = 3×4⁰ + 51 = 63 = 9×7
∴ S₀ is divisible by 9
Since
-
is divisible by 9, we have;
-
=
-
is divisible by 9
Therefore
is divisible by 9 and
is divisible by 9 for all positive integers n
Step-by-step explanation:
A)
The question tells us that
y + z = 180
And
y=3x+20
z=x
So we put them in the first formula:
y + z = 180
(3x + 20) + x = 180
Add and get x to one side:
4x + 20 = 180
4x + 20 - 20 = 180-20
4x = 160
Divide both sides by 4
x = 40
B)
Put x back in to equation to get size of each angle:
Y =3x +20
Y=3(40)+20
Y=120+20
Y=140
Z=x
Z=40
Verify: y+z=180
140+40=180
180=180
<span>5x= 6x^2 -3
</span><span>6x^2 -5x -3
a = 6
b = -5
c = -3
x = [-b +- sq root(b^2 -4ac)] / 2a
x = [--5 +- </span><span>sq root (25 -(4*6*-3)] / 12
</span><span>x = [5 +- sq root (25 + 72)] / 12
x = [5 + sq root (97)] / 12
x = 5 +- </span><span>9.84886] / 12
x1 = </span><span><span><span>1.237405
</span>
</span>
</span>
<span>
x2 = </span><span><span><span>-0.404072
</span>
</span>
</span>