Answer:
4.31 kilometer
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There are 5 solutions for this system.
x^2 + 4y^2 = 100 ____1
4y - x^2 = -20 ____2
Add both 1 & 2 together. x^2 gets cancelled
4y^2 + 4y = 80 (send 80 to the other side and divide by 4)
Then equation the becomes : y^2 + y -20 =0
Now factorise the equation: (y+5) (y-4) = 0
Solve for y : y = -5 and y = 4
Using the values of y to find the values of x. From equation 1:
x^2 = 100 - 4y^2 x = /100 - 4y^2 (/ means square root) Replace values of y
y = -5, x = /100 - 4(-5)^2 = /100 - 100 = 0
y = 4, x = /100 - 4(4)^2 = / 100 - 64 = /36 = -6 or 6
Thus we have 6 solutions y = -5, 4 and x = -6, 0, 6
Answer:
x + y = 8
20x + 110y = 340
Step-by-step explanation:
Answer:
The y-intercept is at the point (0, 9).
Step-by-step explanation:
WE have the y intercept when x = 0:
-7(0) - 5y = -45
-5y = -45
y = -45/-5 = 9.
Answer:
2x^2-12x-54
Step-by-step explanation:
First 2x times x along with 2x times -9
Second 6 times x along with 6 times -9
2x^2-18x+6x-54
=2x^2-12x-54
