5x + y = 9....multiply by 7
10x - 7y = -18
----------------
35x + 7y = 63 (result of multiplying by 7)
10x - 7y = -18
----------------add
45x = 45
x = 45/45
x = 1
5x + y = 9
5(1) + y = 9
5 + y = 9
y = 9 - 5
y = 4
solution is : (1,4)
=========================
-4x + 9y = 9
x - 3y = -6 ....multiply by 4
----------------
-4x + 9y = 9
4x - 12y = -24 (result of multiplying by 4)
---------------add
- 3y = - 15
y = -15/-3
y = 5
x - 3y = -6
x - 3(5) = -6
x - 15 = -6
x = -6 + 15
x = 9
solution is : (9,5)
B) -23 because a double negative is a positive so it’s -35 + 12 which is -23
Answer:
Step-by-step explanation:
Hello There!
Once again we need to isolate the variable using inverse operations
to get rid of the -8.2 we add 8.2 to each side
-8.2+8.2 cancels out
-9.7+8.2=-1.5
now we have
-1.2z>-1.5
now we wan to get rid of the -1.2
to do so we want to divide each side by -1.2
Remember we have to flip the inequality sign because we're dividing by a negative number
we're left with
z<1.25
Answer:
a. x<7 and x>-7
Step-by-step explanation:
√x²<√49
-7<x<7 hope this helps
Answer:
B
Step-by-step explanation:
The problem is simple because they use powers of 10. When something is multiplied by a power of ten, it is essentially moving the decimal point over for every power.
9.46x10^12= 9460000000000
4.0x10^13= 40000000000000
Although 4 itself is less than 9.46, since is is being multiplied by 10^13, it will be one decimal place bigger.
