Answer:
multiply either sides by 3:
divide either sides by πr² :
3x + 5 > 11
3x + (5 - 5) > 11 - 5
3x > 6
3x / 3 > 6 / 3
x > 2
x - 3 < 1
x (-3 + 3) < 1 + 3
x < 4
When subtracting / adding values to both sides, the inequality does not change.
When multiplying / dividing by a positive value, the inequality also doesn't change, but when multiplying , dividing with a negative value, the inequality must be flipped.
Answer:
A
Step-by-step explanation:
Remark
f and d are equal (and acute) because they are corresponding angles.
82 and f are supplementary, so we can find f
Finding f
f + 82 = 180
f = 180 - 82
f = 82
Finding d
d = f
d = 82
I would personally take the number three and trow it out the window but that's not what we are talking about
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
