Answer:
The number is 18
Step-by-step explanation:
You can write an equation to represent this. Let x represent the unknown number.
3x - 18 = 2x
Move 2x to the left side. Remember, "change the side, change the sign." Add 0 as a placeholder to the right of the equals sign.
3x - 2x - 18 = 0
Simplify like terms.
x - 18 = 0
Move -18 to the right of the equals sign.
x = 18
Now that we know x = 18, we can substitute it into the problem.
"Eighteen less than three times 18 is two times 18."
18 x 3 = 54
54 - 18 = 36
36 is, in fact, two times 18. We can check this by dividing 36 by 2.
36 ÷ 2 = 18
Answer:
X=9 and X=5
Step-by-step explanation:
So you want to get one side to equal zero so you can factor and find x. I recommend subtracting 14x and adding 45 to both sides so you don't have to deal with a negative quadratic.
X^2 - 14X +45 = 0
Now you can factor. Your looking for two factors that equal 45 and add to -14
All factors of 45:
1 and 45, 3 and 15, 5 and 9, -1 and -45,
-3 and -15, -5 and -9
So out of those combinations -5 and -9 both multiply to 45 and add up to -14 so these are our common factors
(X-5)(X-9)=0
X-5=0 add 5 to both sides X=5
X-9=0 add 9 to both sides X=9
y=7x-5 This is the same as saying y-7x = -5 Well easy. You just make up numbers that make this work. Let x be 1 y-7=-5 y=-5+7 y=2 So one ordered pair is (1,2) Let x=2 y-14=-5 y=9 So another ordered pair is (2,9) Let x=3 y-21=-5 y=-5+21 y=16 So another ordered pair is (3,16)
hope it helps
