Answer: We have c = 3 and d = -2
Step-by-step explanation:
We want to solve the equation:
6200.07 = 6.2x10^c + 7x10^d
First, we can separate the left number into two pieces:
6200.07 = 6200 + 0.07 = 6.2x10^c + 7x10^d
Now we can solve it as:
6200 = 6.2x10^c
6200/6.2 = 10^c
1000 = 10^c
now we can use that if y = a^x, then ln(y)/ln(a) = x
here we have:
c = ln(1000)/ln(10) = 3
and
0.07 = 7x10^d
0.07/7 = 10^d
0.01 = 10^d
d = ln(0.01)/ln(10) = -2
If <em>y</em> = <em>x</em> and <em>y</em> = <em>z</em>, then by substitution we can say <em>x</em> = <em>z</em>.
In this case, substitution gives us
-1/2 <em>x</em> - 2 = -3/2 <em>x</em> + 2
and we can solve for <em>x</em> :
3/2 <em>x</em> - 1/2 <em>x</em> = 2 + 2
<em>x</em> = 4
then solve for <em>y</em> :
<em>y</em> = -1/2 <em>x</em> - 2
<em>y</em> = -1/2 * 4 - 2
<em>y</em> = -2 - 2
<em>y</em> = -4
The answer to your question is B
Answer:
D∪∪
Step-by-step explanation:
x²+x-72=0
x²+9x-8x-72=0
x(x+9)-8(x+9)=0
(x+9)(x-8)=0
x=-9,8
