All categories

3 years ago

Find the value of y when x equals 1, 9x+7y=-12

Mathematics

1 answer:

SpyIntel [72]3 years ago

3 0

9(1)+7y=-12
9+7y=-12
7y=-12-9
7y=-21
y=-3

You might be interested in

Find <img src="https://tex.z-dn.net/?f=a_%7B1%7D" id="TexFormula1" title="a_{1}" alt="a_{1}" align="absmiddle" class="latex-form

yKpoI14uk [10]

Answer:

$\displaystyle a_{1} = 108$

Step-by-step explanation:

we are given

the sum,common difference and nth term of a geometric sequence

we want to figure out the first term

recall geometric sequence

$\displaystyle S_{ \text{n}} = \frac{ a_{1}(1 - {r}^{n} )}{1 - r}$

we are given that

$S_n=189$
$r=\dfrac{1}{2}$
$n=3$

thus substitute:

$\displaystyle 189= \frac{ a_{1}(1 - {( \frac{1}{2} )}^{3} )}{1 - \frac{1}{2} }$

to figure out $a_1$ we need to figure out the equation

simplify denominator:

$\displaystyle \frac{ a_{1}(1 - {( \frac{1}{2} )}^{3} )}{ \dfrac{1}{2} } = 189$

simplify square:

$\displaystyle \frac{ a_{1}(1 - {( \frac{1}{8} )}^{} )}{ \dfrac{1}{2} } = 189$

simplify substraction:

$\displaystyle \frac{ a_{1} (\frac{7}{8} )}{ \frac{1}{2} } = 189$

simplify complex fraction:

$\displaystyle a_{1} (\frac{7}{8} ) \div { \frac{1}{2} } = 189$

calculate reciprocal:

$\displaystyle a_{1} \frac{7}{8} \times 2 = 189$

reduce fraction:

$\displaystyle a_{1} \frac{7}{4} \ = 189$

multiply both sides by 4/7:

$\displaystyle a_{1} \frac{7}{4} \times \frac{4}{7} \ = 189 \times \frac{4}{7}$

reduce fraction:

$\displaystyle a_{1} = 27\times 4$

simplify multiplication:

$\displaystyle a_{1} = 108$

hence,

$\displaystyle a_{1} = 108$

4 0

3 years ago

Find the distance between the points (8,-1) and (-4,-6)

Harman [31]

The distance between both points is 13 units.

3 0

4 years ago

I have to find the area of the shape

Alekssandra [29.7K]

The answer is 18m^2. if u find the area of each section and add it up together at the end then u get 18

5 0

4 years ago

Pls help fast im confuse 18 points and brainiest

Darya [45]

Answer:

Step-by-step explanation:

4 0

3 years ago

Identify and explain the error.

sergeinik [125]

Answer:

Step-by-step explanation:

Strictly speaking, 15% isn't precisely the same as 0.15; 0.15 is the decimal fraction used to calculate 15% of some quantity.

15% of 52 is indeed 7.8. $7.80 is the discount that is to be SUBTRACTED from the regular price ($52). Adding $7.80 to $52 is incorrect.

Also, 52 + 7.8 - 59.8 is incorrect: it's not an equation (but should be one), and we should be subtracting $7.80 from $52.

8 0

3 years ago