There are 20 boys in the class. The ratio is 4:3 so that means 4 out of 7 are boys and 3 out of 7 are girls. Divide 35 by 7 and you get 5. 5 times 4 is 20. 5 times 3 is 15. add them together and you have 35 students in total. So 20 students are boys and 15 students are girls.
20x-28+12=16x+24 (i distributed the 4 to get this)
20x-16=16x+24 (added -28 & 12)
4x=40 (Subtracted 16x from both sides and added 16 to both sides)
(divide by 4 on both sides)
x=10
Answer:
The correct option is B.
Step-by-step explanation:
Given information: AB\parallel DCAB∥DC and BC\parallel ADBC∥AD .
Draw a diagonal AC.
In triangle BCA and DAC,
AC\cong ACAC≅AC (Reflexive Property of Equality)
\angle BAC\cong \angle DCA∠BAC≅∠DCA ( Alternate Interior Angles Theorem)
\angle BCA\cong \angle DAC∠BCA≅∠DAC ( Alternate Interior Angles Theorem)
The ASA (Angle-Side-Angle) postulate states that two triangles are congruent if two corresponding angles and the included side of are congruent.
By ASA postulate,
\triangle BCA\cong \triangle DAC△BCA≅△DAC
Therefore option B is correct
Change the messy words into numerals
3 times a number minus 2 equals 13
3 × n - 2 = 13
3n - 2 = 13
take 2 to the other side
3n - 2 + (2) = 13 + (2)
3n = 15
Divide by 3 on either sides to isolate n

=

3 and 3 cancels out
n = 5
check:
3 times 5 minus 2 equals 13
3 × 5 - 2 = 13
15 - 2 = 13
13 = 13
The number is 5
Answer:
x=13
Step-by-step explanation:
if you will substitute the value of f(x) with 5, you will get the following equation:
5=2x-21
2x=26/÷2
x=13
(I didn't know what you ment when you wrote x2, is it x square or 2X)
I really hope it was the second one, cause that's how I solved it.