Answer:
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Step-by-step explanation:
First use 


It doesn't have to be
, it could be
. It will be the same answer.
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You would do 24 times 3 and get 72 or divide 24 by 1/4=0.25
Answer:
Step-by-step explanation:
We can solve this question using proportion
Perimeter of the square/Time is takes to unlock
We are told in the question that:
The cellphone unlocks when the perimeter reaches 32 centimeters, taking a total of 2.5 seconds.
Hence, the perimeter of the square after 1.5 seconds is:.x = unknown
32/2.5 = x/1.5
Cross Multiply
2.5x = 32 × 1.5
x = 32 × 1.5/2.5
x = 19.2 centimeters
I'll assume the above equation is: 9 - 7x = 7 - 4(2x+3)
* do distributive multiplication
9 - 7x = 7 - 8x - 12
*move like terms
-7x + 8x = 7 - 12 - 9
* solve for x
x = 7 - 21
x = -14
To check, substitute x by its value -14
9 - 7x = 7 - 4(2x+3)
9 - 7(-14) = 7 -4[2(-14) + 3]
9 + 98 = 7 - 4(-28 +3)
107 = 7 - 4(-25)
107 = 7 + 100
107 = 107
DX1.21 because 1.21 means 21 percent more than d