Download Algebra I Study Guide 7-1 to 7-5

Algebra I Study Guide 7-1 to 7-5
1. Solve
2. Solve
for x = 2 and y = –4?
3. Solve
for x = 3 and y = –1?
for x = 2 and y = –4?
Simplify.
4.
5.
6.
10.
7.
Simplify.
11.
8.
12.
9.
Simplify.
13.
14.
17.
What is each expression written using each base
only once?
15.
18.
16.
19.
20.
21.
Simplify.
22.
23.
24.
25.
27.
26.
Simplify.
28.
29.
30.
31.
32.
33.
36.
Simplify.
37.
34.
Simplify the expression.
35.
38.
Simplify. Give your answer in scientific notation.
39.
49. Astronomers measure large distances in light-years.
One light-year is the distance that light can travel in
one year, or approximately
miles.
3
1.92

10
Suppose a star is
light-years from Earth.
In scientific notation, approximately how many
miles is it?
40.
41.
42.
43. Write the radical expression
in exponential
form.
44. Write the radical expression
form.
45. Write the exponential expression
form.
46. Write the exponential expression
form.
47. Write the exponential expression
form.
in exponential
in radical
in radical
in radical
48. Radio signals travel at a rate of
meters per
second. How many seconds will it take for a radio
signal to travel from a satellite to the surface of the
Earth if the satellite is orbiting at a height of
meters?
50. Last year, a large trucking company delivered
5.5  105 tons of goods with an average value of
$23,000 per ton. What was the total value of the
goods delivered? Write the answer in scientific
notation.
51. Scientists believe that there is an extremely massive
black hole at the center of the Milky Way. How
many times more massive than the Sun would a
36
black hole with a mass of 7.36  10 kg be? The
30
mass of the Sun is approximately 1.99  10 kg.
52. The radioactive substance strontium-90 has a halflife of 28 years. In other words, it takes 28 years for
half of a given quantity of strontium-90 to decay to
a non-radioactive substance. The amount of
radioactive strontium-90 still present after t years is
modeled by the expression
grams.
Evaluate the expression for t = 0, t = 28 and t = 56.
What does each value of the expression represent?
53. Suppose a white dwarf star has a diameter of
4
approximately 1.8083  10 km. Use the formula
to find the approximate surface area of the
star.
Algebra I Study Guide 7-1 to 7-5
Answer Section
1.
2. 
4
27
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18. 1
19.
20.
21. –5
22.
23.
24.
25.
26.
27.
28.
29.
30.
31. 1
32.
33.
34.
35.
36.
37.
38.
8
39. 4.9  10
1
40. 5.4  10
-10
41. 3 x 10
42. 1.625 x 105
43.
44. z4/5
45.
7
46. √(6𝑥)6
4
47. √𝑦 3
48.
seconds
49. 1.13  10 miles
10
50. 1.265  10 dollars
16
6
51. 3.7  10
52. When t = 0, the value of the expression is 80 g. This is the initial quantity of strontium-90.
When t = 28, the value of the expression is 40 g. This is the amount of strontium-90 remaining after 28 years i.e.,
after 1 half-life.
When t = 56, the value of the expression is 20 g. This is the amount of strontium-90 remaining after 56 years i.e.,
after 2 half-lives.
9
53. 1.03  10 km2