Answer:
(2,-1)
Step-by-step explanation:
Multiply first equation by 2:
10x + 2y = 18
Subtract the second equation from this so that the 2y terms cancel:
10x - 3x = 18 - 4
7x = 14
x = 2
Plug into first equation to find y:
5(2) + y = 9
10 + y = 9
y = -1
The answer is (2,-1)
Two lines are perpendicular if and only if the product of their slopes is - 1.
So, you just need to find the slope of each line and find out the product of their slopes.
I will do one example for you.
L1: y = 3x + 5
L2: y = - 3x + 14
L3: y = -x/3 + 14
The slope of a line is the coefficient of the x.
So the slopes are:
L1: slope 3
L2: slope -3
L3: slope -1/3
So now multiply the slopes of each pair of lines:
L1 and L2: 3 * (-3) = - 9 => No, they are not perpendicular
L2 and L3: (-3) * (-1/3) = 1 => No, they are not perpendicular
L1 and L3: (3) * (-1/3) = -1 => Yes, they are penpendicular.
Depending on how flexibly you interpret "about 20 times larger" to mean, the answers are B and D.
Check the ratios of the larger number to the smaller number:
A: (2.01 x 10^7)/(4.25 x 10^6) = 2.01/4.25 x 10^1 = 20.1/4.25 = 4.729
B: (8.21 x 10^-3)/(4.13 x 10^-4) = 8.21/4.13 x 10^1 = 82.1/4.13 = 19.879
C: (4.91 x 10^6)/(5.09 x 10^3) = 4.91/5.09 x 10^3 = 4910/5.09 = 964.637
D: (5.97 x 10^4)/(3.12 x 10^3) = 5.97/3.12 x 10^1 = 59.7/3.12 = 19.135
Answer:
c
Step-by-step explanation:
Answer:
Time 4 minus 2
Step-by-step explanation:
