X = -8.
subtract 19.
-X = 8
divide by -1.
X = -8
Answer:
4
Step-by-step explanation:
The result is
9
a
2
−
16
The reason is the following:
The problem is an example of a notable product: "the sum multiplied by the diference is equal to the difference of squares", that is to say:
(
a
+
b
)
⋅
(
a
−
b
)
=
a
2
−
b
2
.
By applying this to our question, we obtain that:
(
3
a
−
4
)
⋅
(
3
a
+
4
)
=
(
3
a
)
2
−
(
4
)
2
=
9
a
2
−
16
.
23
Step-by-step explanation:
angle DEF = 74 degrees.
well I would use sins but it's quite simple
Length of DE is 23, just like AB
B = 2x+4
H = 3x-5
A = bh
= (2x+4)(3x-5)
= (2x)(3x)+(2x)(-5)+(4)(3x)+(4)(-5)
= 6x^2 - 10x + 12x - 20
= 6x^2 + 2x - 20
So the answer is A (6x^2 + 2x - 20) (i think)
