Answer:
8
Step-by-step explanation:
40*0.80 = 32
40 - 32 = 8
What is graphing. Just wondering
Answer:
x = -2.5
x = 2
Step-by-step explanation:
Hello!
We can remove the denominators by multiplying everything by it.
Solve:
Let's make one side equal to 0.
Solve by factoring, and then the zero product property.
Multiply 2 and -10. You get -20. Think of two number that multiply to -20, and add to 1. If we think about the standard form of a quadratic,
, think two numbers that equal "ac" and add up to "b".
Using the zero product property, set each factor to 0 and solve for x.
- 2x + 5 = 0
2x = -5
x = -5/2 = -2.5 - x - 2 = 0
x = 2
The two answers are x = -2.5, and x = 2.
The answer is b, because division checks multiplication.
To solve this problem you must apply the following proccedure:
1. You have a total of 21 coins, all nickels and dimes. Then:
x:nickels=5 cents
y: dimes=10 cents
x+y=21
2. You have that the total value is $1.70. Then:
5x+10y=170
3. The system of equation is:
x+y=21 (i)
5x+10y=170 (ii)
4. You have:
x+y=21
x=21-y
5(21-y)+10y=170
105-5y+10y=170
y=13 dimes
x+13=21
x=8 nickels