20x - 30y = -50 ⇒ 20x - 30y = -50
x + 2y = -1 ⇒ <u>20x + 40y = -20</u>
<u>-70y</u> = <u>-30</u>
-70 -70
y = ³/₇
20x - 30(³/₇) = -50
20x - 12⁶/₇ = -50
<u> + 12⁶/₇ + 12⁶/₇
</u> <u>20x</u> = <u>47¹/₇
</u> 20<u /> 20<u>
</u> x = 2⁷/₂₀
(x, y) = (2⁷/₂₀, ³/₇)
(_ , _) means (X , Y)
(25 , ) means
X = 25 then you need find the value of Y from the equation .
so the first answer is (25,-3)
..............
( , -8) means
Y = -8 then you need to find the value of X from the equation .
so the second answer is ( 0 , -8 )
hope this would help you
Answer:
Well B is the base of the shape
If thats what you mean
Step-by-step explanation:
Answer:
(a) (a² +3a -1)(a² -3a -1)
Step-by-step explanation:
The constant term of the product of the factors will be equal to the product of their constants. Since you want that product to be +1, the signs of the factor constants must be the same. That eliminates choices (c) and (d).
__
To tell which of choices (a) and (b) is correct, we can compute the squared term in their product. Let's do it in a generic way, with the constant (±1) being represented by "c".
We want the a² term in the product ...
(a² +3a +c)(a² -3a +c)
That term will be the result of multiplying both sets of first and last terms, and adding the product of the middle terms:
(a²·c) +(a²·c) -9a² = a²(2c-9)
So, we want the factor (2c-9) to be -11, which means c=-1, not +1.
The correct factorization of the given expression is ...
(a² +3a -1)(a² -3a -1) . . . . matches choice A
Answer:
x=6
y=9
z=10
Step-by-step explanation: The long 20 on the left has 4, 6 and _10_ to make 20. The blank which is 10 is the same length as z. The proportion of 10/15 translates throughout the whole shape. That means it is 6/9 and 4/6.
The simplified proportion is 2/3 by the way.
