algebra
posted by Sella on .
mang pedring wanted to construct a square table such that the length of its side is 30 cm longer than its height.
Suppose the area of the table is 2.25m^2, what would be its height?

*I had a correction for the last question you posted:
Q: mang pedring wanted to construct a square table such that the length of its side is 30 cm longer than its height.
What expression represents the area of the table? Suppose the table is 90 cm high what would be the area?
A:
Let x = height of table
Let x+30 = length of table
Recall that area of square is given by
A = L^2
where L = length of one side.
substituting,
A = (x+30)^2
A = x^2 + 60x + 900
If table is 90 cm high, then the length of square is 120 cm. Substituting this to the equation for area,
A = 90^2 + 60(90) + 900
A = 14400 cm^2
*sorry about that! The x value substituted must be 90, not 120.
=====
~for the current question,
Let x = height of the table
let x + 30 = length of table
recall that area of a square is given by
A = L^2
where L = length of one side of square
substituting,
2.25 = L^2
L = sqrt(2.25)
L = 1.5 m
note that 30 cm = 0.3 m, thus,
1.5 = x + 0.3
x = 1.2 m (height)
hope this helps~ :D 
lots of THANK YOU! maraming salamat! :D