Answer:
7 cm
Step-by-step explanation:
An equilateral triangle has all sides equal.
To find the measure of the side, simply divide the perimeter by 3. This is because a triangle has 3 sides.
21 ÷ 3 = 7
To solve this system by substitution, we must substitute in the value we are given for x in terms of y (the first equation) into the second equation. This is modeled below:
x = -8y - 15
2x + 5y = -8
2 (-8y - 15) + 5y = -8
Now, we should solve this new equation for y. To begin, we should use the distributive property to get rid of the parentheses on the left side of the equation and begin the simplification process.
-16y - 30 + 5y = -8
Next, we can combine like terms on the left side of the equation by adding together the two terms that both contain the variable y.
-11y - 30 = -8
Next, we should add 30 to both sides in order to move all of the constant (number) terms to the left side of the equation.
-11y = 22
After that, we should divide both sides of the equation by -11 in order to get the variable y alone.
y = -2
Now, we can substitute our value for y back into one of our original equations (it doesn't matter which one you choose; they will yield the same answer).
x = -8y - 15
x = -8(-2) - 15
To simplify, we should following the order of operations outlined by PEMDAS and compute the multiplication and then the subtraction.
x = 16 - 15
x = 1
Therefore, the answer to the system is x = 1 and y = -2, or (1,-2) when written as an ordered pair.
Hope this helps!
C. 5 units is the answer and I am typing to make in 20 characters long.
Answer:
28.07 and rounded to the nearest hundredth would be 28.10
Step-by-step explanation:
Answer:
8) -8, -9
9) 4, 
Step-by-step explanation:
8) x² + 12x + 27
Solutions of a polynomial means the values of
such that the polynomial becomes zero.
.
We use the following formula to determine the solutions of a quadratic equation of the form: 

In this equation, 
Substituting in the formula, we have:


Taking 2 common outside we get:

Therefore, we get two solutions viz, x = -3, -9.
9) 2x² - 9x + 4 = y
X- intercepts of a polynomial means the value of x such that y = 0. It means the roots of the polynomial.
Solving the equation using the formula above, we get:


The values of x = 4,
.
Hence, the answer.