Answer:
x = 3.25
y =4.75
Step-by-step explanation:
In order to Solve the following system of equations below algebraically using substitution method we say that;
let;
8x - 4y = 7
..................... equation 1
x + y = 8.......................... equation 2
from equation2
x + y = 8.......................... equation 2
x = 8 - y.............................. equation 3
substitute for x in equation 1
8x - 4y = 7
..................... equation 1
8(8-y) - 4y = 7
64-8y-4y=7
64-12y=7
collect the like terms
64-7 = 12y
57= 12y
divide both sides by the coefficient of y which is 12
57/12 = 12y/12
4.75 = y
y =4.75
put y = 4.75 in equation 3
x = 8 - y.............................. equation 3
x = 8 -4.75
x = 3.25
to check if your answer is correct, put the value of x and y in either equation 1 or 2
from equation 2
x + y = 8.......................... equation 2
3.25 + 4.75 =8
8=8.................... proved
To factor, you can first treat it like a single bracket and find the common factor. In this case, the common factor is 3x, so you get
3x(x² + 7x + 12)
Now you can factor the bracket normally, by finding factors of 12 that add up to make 7. The factors would be 3 and 4, so the bracket becomes (x + 3)(x + 4).
This leaves your final answer as
3x(x + 3)(x + 4)
I hope this helps!
The function you seek to minimize is
()=3‾√4(3)2+(13−4)2
f
(
x
)
=
3
4
(
x
3
)
2
+
(
13
−
x
4
)
2
Then
′()=3‾√18−13−8=(3‾√18+18)−138
f
′
(
x
)
=
3
x
18
−
13
−
x
8
=
(
3
18
+
1
8
)
x
−
13
8
Note that ″()>0
f
″
(
x
)
>
0
so that the critical point at ′()=0
f
′
(
x
)
=
0
will be a minimum. The critical point is at
=1179+43‾√≈7.345m
x
=
117
9
+
4
3
≈
7.345
m
So that the amount used for the square will be 13−
13
−
x
, or
13−=524+33‾√≈5.655m
