Turn it into math terms bit by bit. let x be "a number"
8 times a number is 8×x
increased by 9 is +9
7 times a number is 7×x
exceeds is minus
by 15 is =15
now we put it together.
![8 \times x + 9 - 7 \times x = 15](https://tex.z-dn.net/?f=8%20%5Ctimes%20x%20%2B%209%20-%207%20%5Ctimes%20x%20%3D%2015)
solve
Answer:
C. Multiply 3 by 18
Step-by-step explanation:
Susan reads:
1 page in 3 mins
So,
1 page = 3 mins
<u><em>If we want the time for 18 pages, we would multiply both sides by 18</em></u>
So,
18 pages = 3×18 mins
18 pages = 54 mins
Answer:
x=1×10−4
Step-by-step explanation:
we have
-----> equation A
The pH of a given solution is the negative log base 10 of the concentration of hydrogen ions, H+
so
ph=-log[H+]
In this problem we have the concentration of hydrogen ions
[H+] =0.1 M
That means that the pH of the solution will be
ph=-log[0.1]
Rewrite
ph=-log[10^-1]
ph=-(-log10)
Remember that
log10=1
substitute
ph=-(-1)
ph=1
substitute the value of ph in equation A and solve for x
applying property of logarithms
![x=10^{-4}](https://tex.z-dn.net/?f=x%3D10%5E%7B-4%7D)