Answer:
x=1 or x=−9
Step-by-step explanation:
Let's solve your equation step-by-step.
x(x+8)=9
Step 1: Simplify both sides of the equation.
x2+8x=9
Step 2: Subtract 9 from both sides.
x2+8x−9=9−9
x2+8x−9=0
Step 3: Factor left side of equation.
(x−1)(x+9)=0
Step 4: Set factors equal to 0.
x−1=0 or x+9=0
x=1 or x=−9
Intersection
x - 7,0
y - 0,-4
Answer:
X= -3, Y= -1
Step-by-step explanation:
Answer:
x^3-4x^2-5x+3
explanation:
multiply each term in the parentheses by X squared
x(x^2)-4x^2-5x+3
Answer: 12 friends.
Step-by-step explanation:
the data we have is:
Mei Su had 80 coins.
She gave the coins to her friends, in such a way that every friend got a different number of coins, then we have that:
The maximum number of friends that could have coins is when:
friend 1 got 1 coin
friend 2 got 2 coins
friend 3 got 3 coins
friend N got N coins
in such a way that:
(1 + 2 + 3 + ... + N) ≥ 79
I use 79 because "she gave most of the coins", not all.
We want to find the maximum possible N.
Then let's calculate:
1 + 2 + 3 + 4 + 5 = 15
15 + 6 + 7 + 8 + 9 + 10 = 55
now we are close, lets add by one number:
55 + 11 = 66
66 + 12 = 78
now, we can not add more because we will have a number larger than 80.
Then we have N = 12
This means that the maximum number of friends is 12.