Answer:
x = -8/5
Step-by-step explanation:
-3(x+4) -> -3x-12
-3x-12=7x+4
-7x
-10x-12=4
+12
-10x=16
16/-10 = -8/5
-8/5 = x
Answer: 2.5
Step-by-step explanation:
y = rx
substitute numbers in and solve for r
if
y = 10
x = 4
then
10 = r4
r = 10/4 = 2.5
this works for all the other numbers and always gives r = 2.5
Step-by-step explanation:
1st digit is 1 number (1)
2nd digit is (3,4,5) so it's 3 numbers
third digit is (6,7,8,9) is it's 4 numbers
last 7 digits is 10 (0,1,2,3,4,5,6,7,8,9)
multiply
1*3*4*10=120
so answer is 120 phone numbers
The digit 7 would be ten times greater than the digit 7 in number 0.9750 in any number with 7 in the tenths place, for example
0.723
0.7669
0.775
1.7899
Okay so lets call Leah "L" and her cousin "C". We know that L+C=36 ... we also know that Leah is twice her cousins age. Therefore, L=2 times C, or L=2C. This is because Leah's age is equivalent to twice as much as her cousin's.
Now that you know that L=2C, you can plug this back into the equation. This should make it so that's there's only one variable now!
L+C=36
(2C)+C=36 ... here we subbed in L=2C
3C=36 ... we add up the C's
C=12 ... we isolate for C by dividing both sides by 3
So her cousin's age is 12 years old. Leah's age is twice that. Thus, she's 24. If you add the two up: 12+24, you indeed get 36. Hope that helps :))
