IDNLearn.com connects you with experts who provide accurate and reliable answers. Get accurate and comprehensive answers to your questions from our community of knowledgeable professionals.

solve this system of equation by substitution
-2x-y=-9
5x-2y=18


Sagot :

-2x - y = -9
y = -2x + 9

5x-2(-2x + 9) = 18
5x - (-4x +18) = 18
9x -18 = 18
9x = 36
x=4

-2x - y = -9
-2(4) - y = -9
-8 - y = -9
-y = -1
y = 1
Point of intersection: (4,1)

[tex]\begin{cases} -2x-y=-9 \\ 5x-2y=18 \end{cases}\\\\ \begin{cases} y=-2x+9 \\ 5x-2y=18 \end{cases}\\\\substitution \\\\ 5x-2 \cdot (-2x+9)=18 \\5x+4x-18=18 \\9x-18+18\\9x=36\ \ /:9\\x=\frac{36}{9}\\x=4\\=================\\y=-2x+9 \\y=-2 \cdot 4+9 =-8+9=1\\ \\Answer:\\\\\begin{cases} x=4 \\ y=1 \end{cases}[/tex]
We appreciate every question and answer you provide. Keep engaging and finding the best solutions. This community is the perfect place to learn and grow together. Your questions deserve accurate answers. Thank you for visiting IDNLearn.com, and see you again for more solutions.