Answer:
<em>The value of the expression for x=3 is 51</em>
Step-by-step explanation:
<u>Evaluating expressions</u>
To evaluate a given expression, we simply substitute the value of the variables and complete the operations.
The expression to evaluate is:
P=3(2+5x)
We will evaluate for x=3:
P=3(2+5*3)
The product must be done first:
P=3(2+15)=3*17=51
The value of the expression for x=3 is 51
<h3>Proof:</h3>
Refer to the attached figure.
There are a couple of ways you can go at this. One is to show the sums of the marked angles are the same, hence ∠B ≅ ∠D. Instead, we're going to show that ΔABD ≅ ΔCDB, hence ∠A ≅ ∠C.
1. AB║DC and BC║AD . . . . given
2. BD is a transversal to both AB║DC and BC║AD . . . . given
3. ∠CBD ≅ ∠ADB . . . . alternate interior angles where a transversal crosses parallel lines are congruent
4. ∠CDB ≅ ∠ABD . . . . alternate interior angles where a transversal crosses parallel lines are congruent
5. BD ≅ BD . . . . reflexive property of congruence
6. ΔABD ≅ ΔCDB . . . . ASA postulate
7. ∠A ≅ ∠C . . . . CPCTC
∠A and ∠C are opposite angles of parallelogram ABCD, so we have shown what you want to have shown.
Answer:
10
Step-by-step explanation:
We'll note the numbers as 

Answer:
289 yards
Step-by-step explanation:
All you have to do is 1156 yards divided by 4 to get a grand total of 289 yards per side
Answer:
30
Step-by-step explanation:
since the width is 20, there are 2 sides, so multiply by 2 and it's 40. Subtract 40 from 100 and you get 60. 60 is both lengths combined, so divide by 2 and you have 30 as your length. :)