first, you take the y = -2x and plug that into y = x + 3. so your equation should be -2x = x + 3. you then solve for x which comes out to be -1. you then plug the -1 into y = -2x. your equation should be y = -2(-1). solve for y which equals 2. the point that you got from both equations matches the point from the equation given so it is true.
It's 154.687 because first you have to line up the dot which is call and. And you going to add your place holder which is a 0 next to the 2 and the you times