Answer:
Step-by-step explanation:
Method 1: Taking the log of both sides...
So take the log of both sides...
5^(2x + 1) = 25
log 5^(2x + 1) = log 25 <-- use property: log (a^x) = x log a...
(2x + 1)log 5 = log 25 <-- distribute log 5 inside the brackets...
(2x)log 5 + log 5 = log 25 <-- subtract log 5 both sides of the equation...
(2x)log 5 + log 5 - log 5 = log 25 - log 5
(2x)log 5 = log (25/5) <-- use property: log a - log b = log (a/b)
(2x)log 5 = log 5 <-- divide both sides by log 5
(2x)log 5 / log 5 = log 5 / log 5 <--- this equals 1..
2x = 1
x=1/2
Method 2
5^(2x+1)=5^2
2x+1=2
2x=1
x=1/2
Answer:
add up c
Step-by-step explanation:
Answer:
C, 15
Step-by-step explanation:
i looked it up
2.5y + 3x = 27
5x - 2.5y = 5
Align the variables to make solving this easier.
2.5y + 3x = 27
-2.5y + 5x = 5
You can see that the 2.5y and -2.5y cancel each other out. Then add the 3x and 5x, and 27 + 5.
3x = 27
5x = 5
8x = 32
Divide both sides by 8.
x = 4
Now input that x into one of the equations to get y.
2.5y + 3(4) = 27
2.5y + 12 = 27
2.5y = 15
y = 6
The answer to this system of equations is x = 4, y = 6. (4, 6)