Answer:
the answer is (A)
Step-by-step explanation:
Answer:
The unique solution to the system is (x,y){(-9,-3)}
Step-by-step explanation:
x - y = -6 equation 1
5x + 6y = -63 equation 2
We will find the value of x from equation 1.
x= y-6
Now put the value of x in equation 2.
5(y-6)+6y = -63
5y-30+6y = -63
Combine the like terms:
5y+6y= -63+30
11y = -33
Divide both sides by 11.
11y/11 = -33/11
y = -3
Now put the value y = -3 in x=y-6
x = y-6
x= -3-6
x= -9
Therefore The unique solution to the system is (x,y){(-9,-3)} ....
This is a system of equations. You can solve it by substitution or elimination. I'm going to use substitution x - 2y = -4.5; add 2y to each side x - 2y + 2y = -4.5 + 2y; simplify x = 2y - 4.5 2(2y - 4.5) + 3y = 12 4y - 9 + 3y = 12 7y - 9 = 12 7y - 9 + 9 = 12 + 9 7y = 21 y = 3 <--------first answer x - 2y = -4.5 x - 2(3) = -4.5 x - 6 = -4.5 x -6 + 6 = -4.5 + 6 x = 1.5 <--------second answer Check: 2(1.5) + 3(3) = 12? 3 + 9 = 12? 12 = 12; It checks 1.5 - 2(3) = -4.5? 1.5 - 6 = -4.5? -4.5 = -4.5; It checks x = 1.5 and y = 3 <-----------Final Answer
Answer:

Step-by-step explanation:

To simplify this expression, first use the distributive property to distribute
.

Simplify.

Combine like terms,
and
.

The simplification of
is
.
I hope this helps ^^
Good luck
Answer:
a. 720
b. 0.3
Step-by-step explanation:
a.
Three balls are selected at random without replacement.
First ball can be selected in 10 ways
Second ball can be selected in 9 ways
Third ball can be selected in 8 ways
Thus, there are 10×9×8 =720 different ways of selecting three balls.
b.
There are three cases that satisfy this condition
- first ball picked is 5, the others are not
- first ball is not 5, second is 5, third is not
- first and second ball is not five, third ball is 5
Each probabilities are:



Thus, one of the balls selected is the number 5 is then 