Answer:
Step-by-step explanation:
hello :
the system is : x+ y =4 ...(*)
2x - y = -1...(**)
add(*) and (**) : 3x=3 so : x=1
put this value into (*) : 1+y=4 so : y=3
one solution : (1 , 3)
Yay, implicit differnentiation
when you take the derivitive of y, you multiply it by dy/dx
example
dy/dx y^2=2y dy/dx
for x, the dy/dx dissapears
ok
so differnetiate and solve for dy/dx
3y² dy/dx-(y+x dy/dx)=0
expand
3y² dy/dx-y-x dy/dx=0
3y² dy/dx-x dy/dx=y
dy/dx (3y²-x)=y
dy/dx=y/(3y²-x)
so at (7,2)
x=7 and y=2
dy/dx=2/(3(2)²-7)
dy/dx=2/(3(4)-7)
dy/dx=2/(12-7)
dy/dx=2/5
answer is 2/5
Answer:
Height = 14.4
Step-by-step explanation:
The diagonals meet at right angles. Interesting property.
The hypotenuse is the side of the rhombus = 15 cm
One of the sides of the small triangles created by the intersection of the diagonals = 24/2 = 12
You can find the other side of the the triangle by using the Pythagorean Theorem
a^2 + b^2 = c^2
c = 15
a = 12
b = ?
12^2 + b^2 = 15^2
144 + b^2 = 225
b^2 = 225 - 144
b^2 = 81
b = 9
The area of this right angle = 9 * 12/2 = 54
There are 4 of them so 4 * 54 = 216
That's the area of the rhombus.
The h= Area / b
b = 15
h = 216/15
h = 14.4
from the question, (-2,2) and (1,2) have the same y value so you can use that as your base and easily find the perpendicular height using the y axis since it's parallel to the x axis.
the third point, (0,-6), to the base is your height
use the sum of the positive of the y values to find your height (because height can't be negative): 6+2 = 8
area of a triangle = 1/2 bh = 1/2 x 3 x 8 = 12
Note: 1/2 bh only works because (-2,2) and (1,2) form a line parallel to the x axis
