Answer:
Step-by-step explanation:
Eight
590 = 1800 e^(-0.4t) Divide by 1800
0.32778 = e^(-0.4t) Put the value for e in the denominator.
0.32778 = 1 / e^(0.4t) Notice the sign's gone. Multiply both sides by e^(0.4t)
0.32778 *e^(0.4t) = 1 Divide by 0.32778
e^(0.4t) = 3.0508 Take the natural log of both sides.
0.4t = 1.11542 Divide both sides by 0.4
t = 2.78855
You should put this in the original equation to see if it checks. It does.
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Nine
3^(3 - 3x) + 6 = 42 Subtract 6 from both sides
3^(3 - 3x) = 36 Take the log of both sides.
(3 - 3x) ln(3) = ln 36
(3 - 3x) *1.098612 = 3.58352 Divide by 1.098612
3 - 3x = 3.26186 Subtract 3 from both sides
- 3x = 0.26186 Divide by - 3
x = - 0.087287
Answer:
The perimeter is 43.6 cm
Step-by-step explanation:
In this question, we are tasked with calculating the perimeter of the sector.
Firstly, we define what a sector is. A sector is part of a circle which is is blinded by two radii and an arc. Hence we say a sector contains two radii.
Thus, to calculate the perimeter of the sector, we need the length of the arc added to 2 * length of the radius
Let’s calculate the length of the arc.
Mathematically, this is theta/360 * 2 * pi * r
where theta is the angle subtended at the middle of the circle which is 135 according to the question, and our radius is 10cm
Thus, we have
135/360 * 2 * 22/7 * 10 = 23.57 cm
Adding two radii to this, we have;
23.57 + 2(10)
= 23.57 + 20 = 43.57 = 43.6 cm to 1 decimal place
<span>x² + y² + 14x − 4y − 28 = 0
x² +14x +y² - 4y =28
x²+2*7x +7² -7² + y² - 2*2y +2² - 2² = 28
(x+7)² + (y-2)² -7²-2² =28
</span>(x+7)² + (y-2)²=28+49+4
(x+7)² + (y-2)² =81 is the answer.
X^3 -2x^2 -35x
=x(x^2-2x-35)
=x(x-7)(x+5)
