Algebra - Suzia, Thursday, September 27, 2007 at 7:52pm
Please explain these problems
5-x-x=-1
a/2+1/5=17
3.5=12x-5x
a-4a=2a+1-5a
Let's look at the first problem.
5 - x - x = -1
It means that you're subtracting a number twice from 5 and getting -1.
What number times 2 can be subtracted from 5 to get -1?
How about 3?
5 - 3 = 2
2 - 3 = -1
Or you can do it algebraically:
5-x-x = -1
6 = 2x
3 = x
If you post the answers to the other problems, we'll be glad to check them for you.
a-4a=2a+1-5a
lil wayne
Sure! Let's go through each problem step by step:
1) 5 - x - x = -1
To solve this equation, we need to combine like terms on the left side and isolate x.
First, let's simplify the left side of the equation:
5 - x - x = -1
Combine the x terms:
5 - 2x = -1
Next, let's isolate x by getting rid of the constant term on the left side.
Subtract 5 from both sides of the equation:
5 - 5 - 2x = -1 - 5
-2x = -6
Finally, solve for x by dividing both sides of the equation by -2:
-2x / -2 = -6 / -2
x = 3
Therefore, the solution to the equation 5 - x - x = -1 is x = 3.
2) a/2 + 1/5 = 17
To solve, we need to find a common denominator and combine the fractions.
Start by finding a common denominator for 2 and 5, which is 10.
Rewrite the fractions with the common denominator:
5a/10 + 2/10 = 17
Combine the fractions on the left side:
(5a + 2) / 10 = 17
Multiply both sides of the equation by 10 to get rid of the denominator:
10 * [(5a + 2) / 10] = 10 * 17
5a + 2 = 170
Subtract 2 from both sides of the equation:
5a = 170 - 2
5a = 168
Finally, solve for a by dividing both sides of the equation by 5:
5a / 5 = 168 / 5
a = 33.6
Therefore, the solution to the equation a/2 + 1/5 = 17 is a = 33.6.
3) 3.5 = 12x - 5x
To solve this equation, we need to combine like terms on the right side and isolate x.
Combine the x terms on the right side of the equation:
3.5 = 12x - 5x
3.5 = 7x
Next, let's isolate x by getting rid of the constant term on the right side.
Subtract 3.5 from both sides of the equation:
3.5 - 3.5 = 7x - 3.5
0 = 7x - 3.5
Finally, solve for x by adding 3.5 to both sides of the equation:
0 + 3.5 = 7x - 3.5 + 3.5
3.5 = 7x
Finally, divide both sides of the equation by 7 to solve for x:
3.5 / 7 = 7x / 7
0.5 = x
Therefore, the solution to the equation 3.5 = 12x - 5x is x = 0.5.
4) a - 4a = 2a + 1 - 5a
To solve this equation, we need to combine like terms on both sides and isolate a.
Combine the a terms on the left side and the constant terms on the right side:
-3a = -3a + 1
Next, let's combine the terms on the right side by subtracting -3a from both sides of the equation:
-3a + 3a = -3a + 1 - 3a
0 = 1 - 3a
Finally, subtract 1 from both sides of the equation to isolate -3a:
0 - 1 = 1 - 3a - 1
-1 = -3a
To solve for a, divide both sides of the equation by -3:
-1 / -3 = -3a / -3
1/3 = a
Therefore, the solution to the equation a - 4a = 2a + 1 - 5a is a = 1/3.