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 :)
Answer:
153.95 feet²
Step-by-step explanation:
Area = pi × r²
radius= 7ft (half of diameter)
3.14 × 7 × 7= 153.95
Standard quadratic equation .. y = a x^2 + b x + c
<span>parabola 'a' not equal to zero </span>
<span>a<0 parabola opens downward </span>
<span>a>0 parabola opens upward </span>
<span>when |a| >>0 the parabola is narrower </span>
<span>when |a| is close to zero , the parabola is flatter </span>
<span>when the constant is varied it only effects the vertical position of the parabola , the shape remains the same</span>
Answer:
Step-by-step explanation:
The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined. y=6 is a straight line perpendicular to the y-axis at point (0,6) , which means that the range is a set of one value {6} .
Answer:
GCF= 1
LCM= 1680
Step-by-step explanation:
GCF= Find the prime factorization of 21, 21 = 3 x 7
Find the prime factorization of 80, 80 = 2 x 2 x 2 x 2 x 5
Then multiply the prime factors both numbers have in common
LCM= multiply the two numbers together and ignore all negative signs
