Before we begin, remember the following:
-ve * -ve = +ve
-ve * +ve = -ve
+ve * -ve = -ve
+ve * +ve = +ve
Now, for each of the given expression, we will expand the brackets, combine like terms and then compare the final output with the given expressions.
First expression:
(x² + 15x + 65) + (2x - 5)(3x + 8)
x² + 15x + 65 + (2x*3x + 2x*8 - 5*3x - 5*8)
x² + 15x + 65 + (6x² + 16x - 15x - 40)
x² + 15x + 65 + 6x² + 16x - 15x - 40
x²(1+6) + x(15+16-15) + 65-40
7x² + 16x + 25
This expression corresponds to letter B
Second expression:
(4x + 1)(3x - 4) - (5x² - 10x - 12)
4x(3x) + 4x(-4) + 1(3x) + 1(-4) - (5x² - 10x - 12)
12x² - 16x + 3x - 4 - 5x² + 10x + 12
x²(12-5) + x(-16+3+10) - 4+12
7x² - 3x + 8
This expression corresponds to letter D
Third expression:
(8x² + 19x + 4) + (3x + 2)(x - 5)
8x² + 19x + 4 + (3x*x + 3x*(-5) + 2*x + 2*(-5))
8x² + 19x + 4 + (3x² - 15x + 2x - 10)
8x² + 19x + 4 + 3x² - 15x + 2x - 10
x²(8+3) + x(19-15+2) + 4-10
11x² + 6x - 6
This is equivalent to letter A
Fourth expression:
(6x + 1)(3x - 7) - (7x² - 34x - 20)
6x(3x) + 6x(-7) + 1(3x) + 1(-7) - (7x² - 34x - 20)
18x² - 42x + 3x - 7 - 7x² + 34x + 20
x²(18-7) + x(-42+3+34) - 7+20
11x² - 5x + 13
This is equivalent to letter C
Hope this helps :)
24+11=35
24-11=13
so it's 24 & 11
To find surface area, we can use the equation:
SA=2lw+2wh+2lh, where:
l=10 in
w=3 in
h=7 in
SA=(2)(10)(3)+(2)(3)(7)+(2)(10)(7)
SA=60+42+140
SA=242 in²
Answer: b. 14ft
Step-by-step explanation:
In the rectangle, the opposite sides are equal. The diagonal divides the rectangle into two equal right angle triangles. The diagonal represents the hypotenuse of both right angle triangles. The length and width represents the opposite and adjacent sides of the right angle triangles.
To determine the length, L of the rectangle, we would apply Pythagoras theorem which is expressed as
Hypotenuse² = opposite side² + adjacent side²
Therefore,
16² = L² + 7²
256 = L² + 49
L² = 256 - 49 = 207
L = √207
L = 14.38
the closest to the length of this rectangle in feet is
14ft
Answer:
Check pdf
Step-by-step explanation:
