Prof. schaben asks her students to simplify this expression: 21 space plus space 15 space divided by space 3. cecilia's answer is 12. is this the correct answer? why or why not?

Cecilia's answer is 12 which is incorrect. The correct answer is 26.

Step-by-step explanation:

Given:

Prof. Schaben asks her students to simplify this expression:

21 space plus space 15 space divided by space 3.

Cecilia's answer is 12.

Now, to find whether the answer is correct or not.

As the expression given:

21 space plus space 15 space divided by space 3.

21 + 15 ÷ 3.

So, we solve it by using the PEMDAS rule:

According to P E M D A S first is division then addition.

Thus, the solution will be as:

Hence, the correct answer is 26.

Therefore, Cecilia's answer is 12 which is incorrect. The correct answer is 26.

50x5=$250

step-by-step explanation:

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.