Answer: OPTION C (119π cm²)
Step-by-step explanation:
Yon can use the following formula for calculate the surface area of a cone:
Where r is the radius and l is the slant height.
Based on the figure shown attached, you have that:
Therefore, when you susbtitute these values into the formula shown above, you obtain that the surface area of the cone is:
cm²
Expression consist of numbers, variables, and mathematical operations. The equation that is true is x²+mx+m= (x+2)².
<h3>What is an Expression?</h3>In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
As it is given that the x²+mx+m is a perfect square trinomial, and we know that the general equation of perfect square trinomial is given as,
ax²+bx+c=0
where a,b and c are real numbers, and a≠0,
if we compare the equation with our equation
We will get the value of 'a' as 1, b=c=m, therefore, we need a binomial which is when expanded then in its perfect square trinomial the value of b=c, therefore, the only feasible option here is (x+2)².
Hence, the equation that is true is x²+mx+m= (x+2)².
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