<span>4x + 3y = 16
7x + 6y = 31
Note what happens if we mult. the first eqn. by -2:
-8x - 6y = -32
Combining this with the 2nd equation eliminates the variable y:
</span>-8x - 6y = -32<span>
7x + 6y = 31
--------------------
-x = -1, or x = 1. Sub 1 for x in either of the 2 given eqns to find y:
For example: 4(1) + 3y = 16, so 36 = 12, and y = 3. Sol'n is (1,3).</span>
Answer:
4th option
Step-by-step explanation:
x² - 2x - 3 = 0 ( add 3 to both sides )
x² - 2x = 3
using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 1)x + 1 = 3 + 1
(x - 1)² = 4
Answer:
Step-by-step explanation:
That will be a square with a diagonal of 20
side length of 20sin45
and area of (20sin45)² = 200 units²
prove it you say?
Area of a rectangle is base times height
A = bh
With a radius of 10, the diagonals of any rectangle inscribed will be 20 units
20² = b² + h²
h = 
A = bh
A = b
Area will be maximized when the derivative is set to zero
dA/db =
- b²/ 
0 =
- b²/ 
b²/
= 
b² = 400 - b²
2b² = 400
b² = 200
b = 
h = 
h = 
h = 
A = bh
A =
•
A = 200 units²
Answer:4 possible rectangles.
Step-by-step explanation:
With all whole numbered dimensions and area of 30sq m is possible when :
Length.width=5*6, 10*3, 15*2,30*1