1. 4x = 7(x - 3) 1.Given
4x = (7)(x) + (7)(-3)
2. 4x = 7x - 21 2.Distributive property
4x - 7x = 7x - 7x - 21
3. -3x = -21 3.Subtraction property of equality
-3x : (-3) = -21 : (-3)
4. x = 7 4.Division property of equality
Answer:
40 girls
Step-by-step explanation:
Set up a proportion where x is the number of girls in band class:
= 
Cross multiply and solve for x:
3x = 120
x = 40
So, there were 40 girls in band class.
Answer:
see explanation
Step-by-step explanation:
Given the rule (x, y ) → (x + 5, - y )
Add 5 to the original x- coordinate and make the y- coordinate negative.
(a)
(5, 3 ) → (5 + 5, - 3 ) → (10, - 3 )
(b)
(- 2, 7 ) → (- 2 + 5, - 7 ) → (3, - 7 )
Answer:
Step-by-step explanation:
You need to use distributive property and multiply each term of the binomial "3x+7" (that is 3x, and 7) by each term of the trinomial "
" taking care of their appropriate signs, and then combine like terms until there is no more than one term for each power of "x". It is also customary to order the final terms in descending order of power of "x".
Let's start by multiplying as indicated above:
![(2x^2+5x-3)*(3x+7)=\\=2x^2\,*\,3x+2x^2\,*\,7\,+5x*3x+5x*7-3*3x-3*7=\\=6x^3+14x^2+15x^2+35x-9x-21=\\=6x^3+[14x^2+15x^2]+[35x-9x]-21=\\=6x^3+29x^2+26x-21](https://tex.z-dn.net/?f=%282x%5E2%2B5x-3%29%2A%283x%2B7%29%3D%5C%5C%3D2x%5E2%5C%2C%2A%5C%2C3x%2B2x%5E2%5C%2C%2A%5C%2C7%5C%2C%2B5x%2A3x%2B5x%2A7-3%2A3x-3%2A7%3D%5C%5C%3D6x%5E3%2B14x%5E2%2B15x%5E2%2B35x-9x-21%3D%5C%5C%3D6x%5E3%2B%5B14x%5E2%2B15x%5E2%5D%2B%5B35x-9x%5D-21%3D%5C%5C%3D6x%5E3%2B29x%5E2%2B26x-21)
She can have 11 rows with 3 in the last row and she can have 6 rows with 3 in the last row
