Answer:
x = approx. 1.24 or -7.24
Step-by-step explanation:
It's hard to factor directly so we should use the quadratic formula or complete the square. I'm going to go with completing the square.
x²+6x-9=0
x²+6x=9
x²+6x is the same as x²+2·3·x, in order to make this into the algebraic identity (A+B)²=A²+2AB+B², we must add B², or in this case 3² to both sides. (A is x, B is 3)
x²+6x+9=18
(x+3)²= 18
x+3= ±√18
x= ±4.24 -3 (approximately 4.24)
First solution for x = 4.24-3 = 1.24
Second solution for x = -4.24-3 = -7.24
87,240. I added them both together.
Sum= addition
-7x -7y = 21
Y = 6
Since they are giving you the value of 6 you just plug it in the equation
-7x - 7(6) = 21
-7x - 42 = 21
+ 42. +42
-7x = 63
/-7. /-7
X = -9
Answer: 231.3 repeating!
Step-by-step explanation: I used the calculator
Answer:
x= 50
Step-by-step explanation:
7/x = 14/100
14x = 700
x = 50
the reason behind my calculations were to get the same ratios and because they gave us percentage and the actual number, we can set them; 14 percent 14/100, however, the 7/x is because we don't know the 100 percent of the coins which is what we look for. Therefore, you cross multiply and get x.
I hope this helped
