Answer:
23 weeks
Step-by-step (x = weeks)
90 + 48 = 138
divide 138 by 6 to find out how many weeks he'd been saving up .
that gives you 23 but to turn it into an equation
6x - 90 = 48
+ 90 +90
6x = 138
_ _
6 6
x = 23 again x meaning weeks
Answer:
10
Step-by-step explanation
The earthquake measures 6.4 on the Richter scale which struck Japan in Jullu 2007 and caused and extensive damage. Earlier that year, a minor earthquake measuring 3.1 in the Richter scale has stroked in parts of Pennsylvania.
Fomular:
The magnitude of an earthquake is M log(I/S)
where I donates the intensity of the earthquake and S be the intensity of the standard earthquake.
Calculation:
Consider that M1 be the magnitude Japanese earthquake and M2 be the magnitude of the Pennsylvania earthquake and L1 be the intensity of the Japanese earthquake and L2 the intensity of the Pennsylvania earthquake.
Here the magnitude of the Japanese earthquake is M1 = 6.14 and the magnitude of the Pennsylvania is M2 = 3.1
By the use of magnitude of the earthquake fomular M = log I1/S, the intensity of the Japanese earthquake is calculated as follows .
M1 = log I1/S
I1/s = 10
We need Pythagoras theorem here
a^2+b^2 = c^2
a, b = legs of a right-triangle
c = length of hypotenuse
Let S=shorter leg, in cm, then longer leg=S+2 cm
use Pythagoras theorem
S^2+(S+2)^2 = (10 cm)^2
expand (S+2)^2
S^2 + S^2+4S+4 = 100 cm^2 [collect terms and isolate]
2S^2+4S = 100-4 = 96 cm^2
simplify and form standard form of quadratic
S^2+2S-48=0
Solve by factoring
(S+8)(S-6) = 0 means (S+8)=0, S=-8
or (S-6)=0, S=6
Reject nengative root, so
Shorter leg = 6 cm
Longer leg = 6+2 cm = 8 cm
Hypotenuse (given) = 10 cm
Answer: Option C
Step-by-step explanation:
Given the quadratic equation 
, substitute 
:
In this case, to find the solutions of the given quadratic equation, you must factor out the variable "x". Then:
Therefore, you get that the solutions of this equation are the following:
Then, the answer is:
This matches with the option C.
Answer:
1) x+5
(4)+5 =
9
2) 3x
3(4)
12
Step-by-step explanation:
