You would evaluate by plugging in the given number of 7 to get your answer.
Can u state the problem it is very blurry thx
It means not to get too invested in details or to become so invested in something that you can’t focus on anything else.
BD = 2x-4
But it's also BE - CE + CD
BE is 3x-1
CE is 2x-3
CD is 2
so
BD = 3x-1 -(2x-3) +2
simplified
BD = 1x +4
since BD = BD (obviously), we can also say that the righthand sides of the two equation must be equal
2x -4 = 1x +4
let's solve for x and that put it into either of the 2 equations.
2x -4 = 1x +4
subtract 1x on both sides
x -4 = 4
add 4 on both sides
x = 8
substitute x for its value in 2x -4 = 1x +4
(this way we double check BD in two expressions at once. the equation should come out true, meaning same value for BD in each expression. both sides should be equal).
2*8 -4 = 1*8 +4
12 = 12
seems true
BD is safely 12
<span>4x^2 - 25
= (2x)^2 - 5^2 .................using a^2 - b^2 = (a+b)(a-b)
= (2x + 5)(2x - 5)</span>