Answer:

Step-by-step explanation:
![\left[\begin{array}{ccc}x + 3y = 7\\x - 3y = 7\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%20%2B%203y%20%3D%207%5C%5Cx%20-%203y%20%3D%207%5Cend%7Barray%7D%5Cright%5D)
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The solution to the system of equations are:

Hope I helped. If so, may I get brainliest and a thanks?
Thank you. Have a good day! =)
The cube root of 81 is 4.32674871092
I'll do the first 2 and 6, and I challenge you to do the other three on your own!
For 1, from some guess and check we can figure out that 5*5=25. Since 5 is a prime number, that's it!
For 2, we can figure out that 7*7=49 and 7 is a prime number, so we're good there.
From 6, we can do some guess and check to figure out that 2*24=48, 2*12=24, 2*6=12, and 2*3=6, resulting in 2*2*2*2*3=48 since 2 and 3 are prime numbers. We found out, for example, to find 2*12 due to that if 2*24=48, 2*24 is our current factorization. By finding 2*12=24, we can switch it to 2*2*12
Hello :
f'(7) = the slope of the tangent line : let A(7,4) B(0,3)<span>
<span>the slope is : (YB - YA)/(XB -XA)= (3-4)/(0-7) = -1/-7 = 1/7=f'(7)
the equation of the tangent line is :
y-3 = 1/7 (x-0)
y = (1/7)x+3
the line tangent and the graph of : f </span></span><span>passes through the point A(7, 4)
x= 7 y=4 so : f(7) =4</span>