Answer:10.9
Step-by-step explanation:You add all of the numbers together (76) and then divide by the total of numbers (7). You will get 10.85714286, you have to round to the nearest 10th , so the 5 changes the 8 to a 9.
Answer:
X=15
Step-by-step explanation:
Yes, you are right.
The given equation is
X+U=25
If U=10, then we substitute to obtain:
X+10=25
Subtract 10 from both sides to get:
X=25-10
Simplify to get:
X=15
The answer is 42.80 , 2.28 is what they saved and i got the .80 cents because i rounded up from .78
Answer:
X= 5, -9
Step-by-step explanation:
(X+2)² =49
Expand the bracket,
(X+2) (X+2)= 49
Apply the distributive property;
X(X+2) +2 (X+2) =49
X²+2X+2X+4=49
X²+4X+4=49
Move 49 to the left side of the equation;
X²+4X+4-49=0
X²+4X-45=0
Apply Factorisation method;
Consider the form
a²+bx+c=0
Find two numbers whose sum is equal to b and whose product is equal to c.
Comparing with our equation;
B =4 and C =45
We can use 9 and -5, this is because ;
9+(-5)=4 and 9*(-5)= 45.
Replace X +4X-45=0 with (X-5) (X+9)=0
Therefore;
X-5=0
X+9=0
Moving to the left side of the equation;
Therefore X= 5 and -9
Recall the logarithm rules :
a^y = x is the same as log_a x = y
In this case,
a = 18
y = r - 10
x = 93
So,
18^ (r-10) = 93
is the same as
log_18 93 = r - 10
Solve for r to get :
10 + log_18 93 = r
