Answer:
a) 
b) 
Step-by-step explanation:
Use logarithm properties:

Then
a) 
b) 
Answer:
3 * 10^6 if the answer is 3.64 * 10^6, you really ought to argue the meaning of estimate with your instructor.
Step-by-step explanation:
This is a very valuable question. Put your calculator away when you answer it. Using a calculator is sort of cheating.
1.3 * 10^3 roughly is roughly 1 * 10^3
2.8*10^3 hours is roughly 3 * 10^3
Forget the powers for now and just work with the 1 and 3
1*3 equals 3.
10^3 * 10^3 = 10^6 when the base of two numbers is the same (10 in this case) then the powers are added.
10^(3 + 3) = 10^6
So the answer is roughly 3*10^6
Now you can take out your calculator and get the answer.
1.3*10^3 * 2.8 * 10^3 = 3.64 * 10 ^ 6
Notice that the estimate (done in my head) is close enough to tell you what the answer should be. On a test, that's a very handy skill.
Answer:
4 hours, $60
Step-by-step explanation:
Assuming "d" is equal to the dollars Jacob earned and h= hours, you start by setting the equations equal to each other, since both are equal to "d."
15h=10h+20
Subtract 10h from both sides (to combine like terms) so the equation becomes:
5h=20
Divide 5 from both sides, to isolate "d" :
h=4
The number of hours Jacob worked is 4, as the equation above shows. To find the amount of money Jacob made, substitute 4 as "h" into the two original equations:
d= 15(4) d=$60
d=10(4)+20 d=$60
Jacob earned $60 dollars in 4 hours.
Answer:
do u want point slope if so y-5=2(x-2)
wStep-by-step explanation:
Answer:
check explanation
Step-by-step explanation:
in eqn 2,
y = 3 - 2x
substitute for it in eqn 1
3x² + y² = 20
3x² + (3 - 2x)² = 20
3x² + 9 - 12x + 4x² = 20
Group like terms;
3x² + 4x² - 12x = 20 -9
7x² - 12x = 11
x(7x - 12) = 11
x = 11,
OR
7x - 12 = 11
7x = 11 + 12
7x = 23
x = 23/7
x = 3.286
To get y, substitute for x in eqn 2
WHEN x = 11,
y = 3 - 2(11)
y = 3 - 22
y = -19
WHEN x = 3.286
y = 3 - 2(3.386)
y = -3.772