Answer:

Step-by-step explanation:
Distribute (2h − 3k)(h + 5k).
2h^2 + 10hk - 3hk - 15k^2
2h^2 + 7hk 15k^2
Recall that
sin(<em>a</em> + <em>b</em>) = sin(<em>a</em>) cos(<em>b</em>) + cos(<em>a</em>) sin(<em>b</em>)
sin(<em>a</em> - <em>b</em>) = sin(<em>a</em>) cos(<em>b</em>) - cos(<em>a</em>) sin(<em>b</em>)
Adding these together gives
sin(<em>a</em> + <em>b</em>) + sin(<em>a</em> - <em>b</em>) = 2 sin(<em>a</em>) cos(<em>b</em>)
To get 14 cos(39<em>x</em>) sin(19<em>x</em>) on the right side, multiply both sides by 7 and replace <em>a</em> = 19<em>x</em> and <em>b</em> = 39<em>x</em> :
7 (sin(19<em>x</em> + 39<em>x</em>) + sin(19<em>x</em> - 39<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
7 (sin(58<em>x</em>) + sin(-20<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
7 (sin(58<em>x</em>) - sin(20<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
Answer:(x-3)(x-4)
Step-by-step explanation:Basically, the intercepts of the graph, 3 and 4, are when the graph is equal to zero, which is why is (x-3)(x-4) and not (x+3)(x+4).
48:24 = 24:12 = 12:6 = 6:3 (divide each number by 2 or multiply by 2)
Answer:
Step-by-step explanation:
Area = 192 m²
Perimeter= 56 m
Width = x m
Perimeter = 56
2*(length + width) = 56
Divide the equation by 2
l + x = 56/2
l + x = 28
l = 28 - x
Area = 192 m²
l * w = 192
(28 - x)*x = 192
28x - x*x = 192
0 = 192 - 28x + x²
x² - 28x + 192 = 0
2) Equation is a quadratic equation. The roots of this equation will the dimensions of the rectangular plot.
3) The roots represent the width and length of the rectangle.
x² - 28x +192 = 0
Sum = -28
Product =192
Factors = -16 , -12 {-16 +(-12) = -28 & (-12)*(-16) = 192}
x² - 28x + 192 = 0
x² - 12x - 16x + (-16)*(-12) = 0
x(x -12) - 16(x - 12) = 0
(x - 12)(x -16) =0
x -12 = 0 ; x - 16 = 0
x = 12 ; x = 16
x = 12 ,16
4) Sum of the roots = 12 + 16 = 28
Sum of the roots = half of the perimeter
5) Product of the roots = 12*16 = 192 = area of the rectangle.