Answer:
A) 14
Step-by-step explanation:
BC is congruent to DC in saying this you can plug the equations to each other and solve for y and then put its back into the equation for BC to get the length.
3y+5=5y-1
subtract 3y from both sides --> 5=2y-1
add 1 to both sides --> 6=2y
now get y alone, divide by 2 by both side --> y=3
plug y in back to 5y-1 --> 5x3-1
15-1
BC = 14
Answer:
Given the equation: 
A quadratic equation is in the form:
where a, b ,c are the coefficient and a≠0 then the solution is given by :
......[1]
On comparing with given equation we get;
a =3 , b = 10
then, substitute these in equation [1] to solve for c;

Simplify:

Also, it is given that the difference of two roots of the given equation is
i.e,

Here,
, ......[2]
.....[3]
then;

simplify:

or

Squaring both sides we get;

Subtract 100 from both sides, we get

Simplify:
-12c = -96
Divide both sides by -12 we get;
c = 8
Substitute the value of c in equation [2] and [3]; to solve 

or
or

Simplify:

Now, to solve for
;

or
or

Simplify:

therefore, the solution for the given equation is:
and -2.
A
explanation:
2x+10=-6-30
8x+40=0
x=-5
Answer:
A
Step-by-step explanation:
the standard form of a quadratic equation is
ax² + bx + c = 0 : a ≠ 0
obtain (5 + x)(5 - x) = 7 in this form by expanding the factors
25 - x ² = 7 ( subtract 7 from both sides )
18 - x² = 0 ( multiply through by - 1 )
x² - 18 = 0 ← in standard form
with a = 1, b= 0 and c = - 18 → A
Answer:
x = 1 , y = 2
Step-by-step explanation:
Solve for substitution