Answer:
A. Z = 2 + N13
Step-by-step explanation:
Let's solve your equation step-by-step.
0=z2+4z−9
Step 1: Subtract z^2+4z-9 from both sides.
0−(z2+4z−9)=z2+4z−9−(z2+4z−9)
−z2−4z+9=0
For this equation: a=-1, b=-4, c=9
−1z2+−4z+9=0
Step 2: Use quadratic formula with a=-1, b=-4, c=9.
z=
−b±√b2−4ac
2a
z=
−(−4)±√(−4)2−4(−1)(9)
2(−1)
z=
4±√52
−2
z=−2−√13 or z=−2+√13
Answer:
x = 12
Step-by-step explanation:
For number 5, the answer is B.
For number 6, the answer is B.
Y are welcome for the help and have a nice day!
Answer: 35.675
Step-by-step explanation:
10.465−(−25.21)
The opposite of −25.21 is 25.21.
10.465+25.21
Add 10.465 and 25.21 to get 35.675.
35.675
Answer:
10m x 15m
Step-by-step explanation:
You are given some information.
1. The area of the garden: A₁ = 150m²
2. The area of the path: A₂ = 186m²
3. The width of the path: 3m
If the garden has width w and length l, the area of the garden is:
(1) A₁ = l * w
The area of the path is given by:
(2) A₂ = 3l + 3l + 3w + 3w + 4*3*3 = 6l + 6w + 36
Multiplying (2) with l gives:
(3) A₂l = 6l² + 6lw + 36l
Replacing l*w in (3) with A₁ from (1):
(4) A₂l = 6l² + 6A₁ + 36l
Combining:
(5) 6l² + (36 - A₂)l +6A₁ = 0
Simplifying:
(6) l² - 25l + 150 = 0
This equation can be factored:
(7) (l - 10)*(l - 15) = 0
Solving for l we get 2 solutions:
l₁ = 10, l₂ = 15
Using (1) to find w:
w₁ = 15, w₂ = 10
The two solutions are equivalent. The garden has dimensions 10m and 15m.
