13a.) If you're dividing and the base (in this case the base is 10) is the same, subtract the exponents.
13b.) If you're multiplying and the base is the same, then you add the exponents:
13c.) This is similar to 13b:
Answer:
x = 64
z = 98
y= 18
Step-by-step explanation:
x = 64
64+z+18 = 180
z = 180-82 = 98
y= 18
Answer:
Ratio = 1 : 4
Step-by-step explanation:
Total marbles = 10
Given 1/5 is red, that is 1/5 of the total marbles are red
Therefore , 10 - 2 = 8 marbles are blue.
Ratio of red marbles to blue marbles
The smallest region that can be photographed is
5*7 = 35 square km
so we want to know how long it takes to zoom out to an area of
35 * 5 = 175 square km.
Notice that the length and width increase at the same rate, 2 km/sec, and they start out with a difference of two, so when the width has increased from 5 to x, the length will have increased from 7 to x+2. At the desired coverage area, then,
x(x+2) = 175
x^2 + 2x = 175
x^2 + 2x + 1 = 176 [completing the square]
(x+1)^2 = 176
x+1 = ±4√11
x = -1 ±4√11
Since a negative value for x is meaningless here, x must be
-1 + 4√11 = about 12.27 km
and the time it took to increast to that value was
(12.27 - 5) km / (2 km/sec) = about 3.63 seconds
