It can be applied by making it sound more educated
<span>What is the value of x in the proportion x + 1 / x+3 = 15/ 21
a.4
b.1/3
c.1/4
d.3</span>
the answer is
a.) 4
Answer:
The equation is 
The value of x is 28 cookies
Step-by-step explanation:
Let
x ----> the number of cookies she baked last week
we know that
The number of cookies she baked last week multiplied by 3 minus 4 must be equal to 80 cookies
so
The linear equation that represent this situation is

solve for x

1. Given
2. Definition of Supplementary Angles
3. First Substitution
4. Subtraction property of Equality
5. Second Substitution
6. Exterior Side in Opposite Rays
7. If corresponding angles are equal, then lines are parallel
Answer:
72
Step-by-step explanation:
If SR and RU have the same length, a right angle, and a shared side, we know that they are congruent triangles using SAS (Side Angle Side). Our equation to find the perimeter would be SR + RU + UT + TS or 16 + 16 + 20 + 20(using our knowledge of the congruent triangles) = 72.