Step-by-step explanation:

Answer:
The third number is 195-3x
Step-by-step explanation:
Given:
sum of three numbers, a, b, c is 180.
a=2x-11
b=x-4
c= ?
Solution:
a+b+c = 180
2x-11 + x-4 + c = 180
c = 180 - (2x-11) - (x-4)
= 180 -2x+11 - x+4
= 180 + 11 + 4 -2x -x
= 195 -3x
Answer:
3
Step-by-step explanation:
3 plates per stack
divide 4 by 4 to get one and 12 by 4 to get 3
Answer:
25 and 57.
Step-by-step explanation:
Let the lowest number be x then the other is 2x + 7, So:
x(2x + 7) = 1425
2x^2 + 7x - 1425 = 0
2 * - 1425 = -2850 = -2 * 3 * 5 * 5 * 19
We need 2 numbers whose product is -2850 and whose sum is + 7.
These are 3 * 19 = 57 and -2* 5 * 5 = -50 so we write:
2x^2 - 50x + 57x - 1425 = 0 Now we factor by grouping:
2x(x - 25) + 57( x - 25) = 0)
(2x + 57) ( x - 25) = 0
x = -57, 25.
We ignore the negative as we are given that the number is positive,
x = 25 is one number and the other is 2(25) + 7 = 57.