The ratio of boys to girls in Anya's class is 10 to 15. There are 20 boys how many girls are there
1 answer:
You might be interested in
Answer:
m=16
Step-by-step explanation:
Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation : 3/4*m-3-(9)=0
Step 1: Simplify 3/4
Equation at the end of step 1: ((3/4 x m) - 3) - 9 = 0
Step2: Subtracting a whole from a fraction
Rewrite the whole as a fraction using 4 as the denominator :
3 3 • 4
3 = — = —————
1 4
Equivalent fraction : The fraction thus generated looks different but has the same value as the whole
Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator
Adding fractions that have a common denominator :
Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
3m - (3 • 4) 3m - 12
—————4——————— = ———4————
When a fraction equals zero ...
Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.
Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.
Here's how:
3•(m-16)
———————— • 4 = 0 • 4
4
Now, on the left hand side, the 4 cancels out the denominator, while, on the right hand side, zero times anything is still zero.
The equation now takes the shape :
3 • (m-16) = 0
6.2 Solve : 3 = 0
This equation has no solution.
A a non-zero constant never equals zero.
Solve : m-16 = 0
Add 16 to both sides of the equation :
m = 16
Answer: The two roots are x = 3/2 and x = -2
=========================================================
Explanation:
You have the right idea so far. But the two numbers should be 3 and -4 since
- 3*(-4) = -12
- 3+(-4) = -1
The -1 being the coefficient of the x term.
This means you need to change the -3x and 4x to 3x and -4x respectively. The other inner boxes are correct.
---------
Refer to the diagram below to see one way to fill out the box method, and that helps determine the factorization.
If we place a 2x to the left of -2x^2, then we need an -x up top because 2x*(-x) = -2x^2
Then based on that outer 2x, we need a -2 up top over the -4x. That way we get 2x*(-2) = -4x
So we have the factor -x-2 along the top
The last thing missing is the -3 to the left of 3x. Note how -3*(-x) = 3x in the left corner and -3*(-2) = 6 in the lower right corner.
We have the factor 2x-3 along the left side.
---------
The two factors are (2x-3) and (-x-2) which leads to the factorization (x+3)(-x+2)
The last thing to do is set each factor equal to 0 and solve for x
- 2x-3 = 0 solves to x = 3/2 = 1.5
- -x-2 = 0 solves to x = -2
The two roots are x = 3/2 and x = -2
