Roberto is x years older than his only sister but 10 years ago he was twice her age. What are the current ages of the siblings?

Mathematics

1 answer:

adell [148]3 years ago

6 0

Answer:

S = x + 10

R = 2x + 10

Step-by-step explanation:

If R is Roberto's age, and S is his sister's age, then:

R = S + x

R − 10 = 2 (S − 10)

Solve with substitution.

S + x − 10 = 2 (S − 10)

S + x − 10 = 2S − 20

S = x + 10

R = 2x + 10

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Evaluate tan45/sin30 . In your final answer, include all calculations.

Maslowich

From the identity $\displaystyle{ \tan x= \frac{\sin x}{\cos x}$ , and from the values:

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3 years ago

Which of the following options is a root of the function? f(x) = (3x + 5) (x2 - 6x + 9)2

Alika [10]

Answer:

The roots of the function are x = -5/3 and 3. Select these.

Step-by-step explanation:

The roots of the function are the solutions to the function. They are also called the x-intercepts or zeros. To find them, factor the function completely and solve using the zero product property.

f(x) = (3x+5)(x2-6x+9)2 becomes f(x) = (3x+5)(x-3)^2

Set each factor equal to 0 and solve for x.

(3x+5)=0

3x = -5

x = -5/3

(x-3)^2 = 0

x - 3=0

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3 years ago

What is the vertex of a parabola having the equation y = –2(x – 5)2 + 7? Which direction does the parabola open?

Vika [28.1K]

$y = -2(x-5)^2 + 7$

That's vertex form for a parabola $y=a(x-p)^2+q$ and we read off vertex (p,q) as

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The negative a tells us this is a downward opening parabola (upside down from the usual $y=x^2$ . I remember CUP - Concave Up Positive; here a is negative so not a cup, instead concave down. The same rule applies to second derivatives in calculus so memorize it now and use it later.