Answer:
Step-by-step explanation:
x + y = 4 ---------------(i)
x = 4-y
7x + 9y = 42 -----------(ii)
Plug in x = 4-y in equ (ii)
7*(4 - y) + 9y = 42
28 - 7y +9y = 42
28 + 2y = 42
2y = 42 - 28
2y = 14
y = 14/2
y = 7
x = 4 - y
x = 4 - 7
x = -3
Answer:
<h3>x = -3 , x = 3</h3>
Step-by-step explanation:
7x² - 3 = 60
7x² - 3 - 60 = 0
7x² - 63 = 0
Simplify the terms
Divide both terms by 7
That's
x² - 9 = 0
Solve the quadratic equation
Use difference of two squares
That's
a² - b² = ( a + b)(a - b)
x² - 9 = 0
(x + 3)(x - 3) = 0
x + 3 = 0 x - 3 = 0
x = - 3 x = 3
Hope this helps you
The applicable formulas for the circumference (C) and area (A) of a circle with diameter d are ...
![\displaystyle C=\pi d\\\\A=\frac{\pi}{4}d^2](https://tex.z-dn.net/?f=%5Cdisplaystyle%20C%3D%5Cpi%20d%5C%5C%5C%5CA%3D%5Cfrac%7B%5Cpi%7D%7B4%7Dd%5E2)
Filling in the given vaue for d, we have
![C=\pi(60\, in)=60\pi \, in\approx 188.5\, in\qquad\mbox{circumference}\\\\A=\dfrac{\pi}{4}(60\, in)^{2}=900\pi\, in^{2}\approx 2827.4\, in^{2}\qquad\mbox{area}](https://tex.z-dn.net/?f=C%3D%5Cpi%2860%5C%2C%20in%29%3D60%5Cpi%20%5C%2C%20in%5Capprox%20188.5%5C%2C%20in%5Cqquad%5Cmbox%7Bcircumference%7D%5C%5C%5C%5CA%3D%5Cdfrac%7B%5Cpi%7D%7B4%7D%2860%5C%2C%20in%29%5E%7B2%7D%3D900%5Cpi%5C%2C%20in%5E%7B2%7D%5Capprox%202827.4%5C%2C%20in%5E%7B2%7D%5Cqquad%5Cmbox%7Barea%7D)
Answer:
are we suposed to pick one
Step-by-step explanation:
i would pick B aka 2