In 12 years it grew 15 feet
X^2-7x-4=0
(x-7/2)^2-(7/2)^2-4=0
(x-7/2)^2-(7)^2/(2)^2-4=0
(x-7/2)^2-49/4-4=0
(x-7/2)^2+(-49-4*4)/4=0
(x-7/2)^2+(-49-16)/4=0
(x-7/2)^2+(-65)/4=0
(x-7/2)^2-65/4=0
(x-7/2)^2-65/4+65/4=0+65/4
(x-7/2)^2=65/4
sqrt[ (x-7/2)^2 ]=+-sqrt(65/4)
x-7/2=+-sqrt(65)/sqrt(4)
x-7/2=+-sqrt(65)/2
x-7/2+7/2=+-sqrt(65)/2+7/2
x=7/2+-sqrt(65)/2
x=[7+-sqrt(65)]/2
x1=[7-sqrt(65)]/2
x2=[7+sqrt(65)]/2
The sign will be positive
Step-by-step explanation:
-2y+4>10
subtract 4 from both sides
-2y+4-4>10-4
-2y>6
divide both sides by two
-2/2y>6/2
-1y>3
if negative y is greater than three than you have to multiply both sides of the equation by -1
y>-3 if you put that back into the earlier equation it is impossible.
so we have to switch the signs to < or less than
y<-3
Hope that helps:)
Answer:
x = 10, y = 0
Step-by-step explanation:
x + y = 10 ---> x = 10 - y
3x + 2y = 30
3 (10 - y) + 2y = 30
30 - 3y + 2y = 30
y = 0
x + 0 = 10
x = 10
