You are solving for b. Isolate the b. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS. First, add 15 to both sides

a (+15) = 4b - 15 (+15)

a + 15 = 4b

Next, divide 4 from both sides. Remember to divide from all terms.

(4a + 15)/4 = (4b)/4

b = (4a)/4 + (15)/4

b = a + 15/4

b = a + 3.75 is your answer

7 0

3 years ago

Please help with the question in the picture!

Stella [2.4K]

Answer:

Tan C = 3/4

Step-by-step explanation:

Given-

∠ A = 90°, sin C = 3 / 5

METHOD - I

Sin² C + Cos² C = 1

Cos² C = 1 - Sin² C

Cos² C = $1 - \frac{9}{25}$

Cos² C = $\frac{25 - 9}{25}$

Cos² C = $\frac{16}{25}$

Cos C = $\sqrt{\frac{16}{25} }$

Cos C = $\frac{4}{5}$

As we know that

Tan C = $\frac{Sin C}{Cos C }$

Tan C = $\frac{\frac{3}{5} }{\frac{4}{5} }$

Tan C = $\frac{3}{4}$ 

METHOD - II

Given Sin C = $\frac{3}{5} = \frac{Height}{Hypotenuse}$

therefore,

AB ( Height ) = 3; BC ( Hypotenuse) = 5

∵ ΔABC is Right triangle.

∴ By Pythagorean Theorem-

AB² + AC² = BC²

AC² = BC² - AB²

AC² = 5² - 3²

AC² = 25 - 9

AC² = 16

AC ( Base) = 4

Since,

Tan C = $\frac{Height}{Base}$ 

Tan C = $\frac{AB}{AC}$

Hence Tan C = $\frac{3}{4}$ 

4 0

3 years ago