Answer:
x=1 and y=4/5
Step-by-step explanation:
<u>Given system of equations</u>
3x+5y=7
5x+10y=13
<u />
<u>Multiply first equation by 2</u>
2(3x+5y)=2(7)
6x+10y=14
<u>Eliminate y-variable to get "x"</u>
6x+10y=14
<u>- 5x+10y=13</u>
x = 1
<u>Substitute x=1 into either equation and find "y"</u>
3x+5y=7
3(1)+5y=7
3+5y=7
5y=4
y=4/5
Therefore, x=1 and y=4/5
21 because it is being multiplied
Answer: f(x) = -0.016x² + 1.6x
Step-by-step explanation:
If the lenght of the road over the arch is 100m, we can consider a coordinate plane and say that the road starts at point (0,0) and finishes at (100,0). The vertice of the parabola is at point (50,40), because the maximum height is 40 and it is always in the middle point of the roots.
So, we have
(0,0) (50,40) (100,0)
A quadratic function is always on the form: f(x) = ax² + bx + c
0 = a0² + b0 + c
40 = a50² + b50 + c
0 = a100² + b100 + c
0 = a0² + b0 + c → c = 0 ∴
40 = a50² + b50
0 = a100² + b100
_________________________
2500a + 50b = 40 (*2)
10000a + 100b = 0
_________________________
5000a + 100b = 80
10000a + 100b = 0 (-)
__________________________
-5000a = 80
-a=80/5000
a=-0.016
∴
2500a + 50b = 40
2500.(-0.016) + 50b = 40
-40 + 50b = 40
50b = 80
b = 80/50
b = 1.6
This way f(x) = -0.016x² + 1.6x
Answer:
-3
Step-by-step explanation:
H = -3
J = -1
J = -1
M=2
(-3+-1)+(-1+2)=-3
Answer:
The two bottom angles of this triangle are both represented by the same variable, in this case, an x. This means, that both of the bottom angles are equal to each other.
So we have:
32 + x + x = 180 (since the TOTAL angles of a triangle adds up to 180)
32 + 2x = 180 (combine the 2 x's together)
2x = 148 (subtract a 32 from both sides)
x = 74
Let me know if this helps!
