Step-by-step explanation:
so, that means we want to find the time t (days) after which N = No/2
because "half-life" means the amount of time until half of the substance has disappeared (or transformed into something else).
so, we have
No/2 = No × e^(-0.1481×t)
No = 2× No × e^(-0.1481×t)
1 = 2×e^(‐0.1481×t)
1/2 = 0.5 = e^(-0.1481×t)
ln(0.5) = -0.1481×t
t = ln(0.5)/-0.1481 = 4.680264555... ≈ 4.7 days
Im assuming you mean 2x^2-3x-9=0 ?
If so, you have to factorise the equation
(2x-3) (x+3) = 0
2x - 3 = 0
2x = 3
x = 1.5
x + 3 = 0
x = -3
x is either 1.5 or -3
Answer:
I think it's "C"
the triangles are nor similar because the variables x and y have different values.
P.S. hope it helped. If you have any questions, I'll be glad to answer them❤
We know that
If a tangent segment and a secant segment are drawn to a circle from an exterior point, then the square of the measure of the tangent segment is equal to the product of the measures of the secant segment and its external secant segment. (Intersecting Secant-Tangent Theorem)
so
ST²=RT*QT
RT=7 in
QT=23+7-----> 30 in
ST²=7*30-----> 210
ST=√210-----> 14.49 in
the answer is
RT=14.49 in
2x - 4y = 10
7x - 9y = 12
_________
9x - 5y = 2
