X = Juan's age
y = Eliza's age
Some key words/phrases we can use to help us make the equation are: 
-is (whatever comes after this word usually equals the end result, or what it equals)
-two years younger
-than
-half her brother's age
.
just break it down :)
x/2 (half her brother's age) - 2 (two years younger) = y (Eliza is...)
| basically,
v
x/2 - 2 = y
So if Juan is 6, then we need to plug in 6 for x.
6/2 - 2 = y
3 - 2 = y
1 = y
ANSWER: Eliza is one year old.
        
             
        
        
        
<span>x² + y² + 14x − 4y − 28 = 0
x² +14x +y² - 4y =28
x²+2*7x  +7² -7²  + y² - 2*2y +2² - 2² = 28
(x+7)² + (y-2)² -7²-2² =28
</span>(x+7)² + (y-2)²=28+49+4
(x+7)² + (y-2)² =81 is the answer.
        
                    
             
        
        
        
Answer:
4
Step-by-step explanation:
The answer is 4
 
        
                    
             
        
        
        
Answer:
C.
Step-by-step explanation:
x^2+20^2=25^2
x^2+400=625
x^2=225
x=15